Pharmaceutical composition for modified release

ABSTRACT

A pharmaceutical composition for modified release comprising (R)-2-(2-aminothiazol-4-yl)-4′-[2-[(2-hydroxy-2-phenylethyl)amino]ethyl]acetic acid anilide or a pharmaceutically acceptable salt thereof, and a carrier for a sustained release pharmaceutical composition, wherein a dissolution rate of the drug from the composition is less than 85% after 30 minutes from the beginning of a dissolution test, is disclosed.

TECHNICAL FIELD

The present invention relates to a pharmaceutical composition formodified release capable of reducing food effects observed inconventional tablets, by combining an active ingredient with one or moreexcipients and controlling a releasing rate of the active ingredient.

More particularly, the present invention relates to a pharmaceuticalcomposition for modified release comprising(R)-2-(2-aminothiazol-4-yl)-4′-[2-[(2-hydroxy-2-phenylethyl)amino]ethyl]aceticacid anilide or a pharmaceutically acceptable salt thereof, and acarrier for a sustained release pharmaceutical composition, in which thechanges of an area under a blood drug concentration versus time curve(AUC) and a maximum blood drug concentration (Cmax) by the intake offood are reduced by controlling a releasing rate of the activeingredient.

BACKGROUND ART

(R)-2-(2-aminothiazol-4-yl)-4′-[2-[(2-hydroxy-2-phenylethyl)amino]ethyl]aceticacid anilide has been created by Astellas Pharma Inc., and it has beenreported that this compound has not only both an activity of promotinginsulin secretion and an activity of enhancing insulin sensitivity, butalso an antiobestic activity and an antihyperlipemic activity based onan activity of selectively stimulating a β3 receptor, and is useful intreating diabetes (see, for example, patent literature 1).

Further, it has been reported that the compound can be used as atherapeutic agent for overactive bladder, such as overactive bladderaccompanied by prostatic hyperplasia, or overactive bladder accompaniedby urinary urgency, urinary incontinence, and urinary frequency (see,for example, patent literature 2).

A clinical trial of(R)-2-(2-aminothiazol-4-yl)-4′-[2-[(2-hydroxy-2-phenylethyl)amino]ethyl]aceticacid anilide in, the form of conventional formulations revealed thatpharmacokinetic data unexpectedly varied according to the presence orabsence of the intake of food. For example, the rate of decrease of Cmaxin a fed state was 67%, and the rate of decrease of AUC in the fed statewas 47%, in comparison with those in a fasted state. In this case, Cmaxin the fasted state was three times higher than that in the fed state.These problems are considered to be raised by, for example, the changesin pharmacokinetics caused by food, and therefore, the development of aformulation capable of avoiding the effects by food intake is desired.

As a technique of preparing a formulation for modified release, ahydrogel sustained release tablet containing an additive which ensurespenetration of water into the tablet, and a hydrogel-forming polymer isdisclosed (see, for example, patent literature 3).

However, patent literature 3 does not refer to(R)-2-(2-aminothiazol-4-yl)-4′-[2-[(2-hydroxy-2-phenylethyl)amino]ethyl]aceticacid anilide, and further improvements are needed to produce apharmaceutical composition.

CITATION LIST Patent Literature

-   [patent literature 1] International Publication No. WO 99/20607    (Example 41)-   [patent literature 2] International Publication No. WO 2004/041276-   [patent literature 3] International Publication No. WO 94/06414

SUMMARY OF INVENTION Technical Problem

An object of the present invention is to provide a pharmaceuticalcomposition for modified release comprising(R)-2-(2-aminothiazol-4-yl)-4′-[2-[(2-hydroxy-2-phenylethyl)amino]ethyl]aceticacid anilide or a pharmaceutically acceptable salt thereof, in which thepharmaceutical composition has efficacy the same as or higher than thoseof conventional formulations and has no limitations on food intake.

Solution to Problem

The elimination half-life (T_(1/2)) of(R)-2-(2-aminothiazol-4-yl)-4′-[2-[(2-hydroxy-2-phenylethyl)amino]ethyl]aceticacid anilide is long (approximately 18 to 24 hours), and thus, aformulation thereof for modified release is not necessarily needed tomaintain its blood level. Taking into consideration the results of theclinical trial described above, the present inventors conductedintensive studies to design the formulation by paying attention to thecontrol of a release rate of the drug from a formulation to the extentthat the release is not affected by food intake or the like, rather thanthe addition of release control.

On the basis of blood concentration profiles (in a fasted state/afterthe intake of food) after administration of a conventional formulation(immediate release formulation), the absorption rate of the drug in afed state was calculated by a deconvolution method to predict continuousabsorption for about 4 hours. The present inventors considered from thisresult that a formulation capable of continuous drug release for 4 hoursor more would be able to reduce the effects by food, because the drugrelease from the formulation would become the rate-limiting step forabsorption.

The present inventors carried out a clinical trial in human using threetypes of formulations in which the release rate of the drug wascontrolled, and found that all formulations could reduce the effects byfood, to complete the present invention.

It is generally known that the retention time in the stomach and therelease rate of formulations for modified release vary according to thepresence or absence of food intake, and as a result, there is apossibility that blood concentration profiles is changed. However,surprisingly, when using this formulation, the change of the bloodconcentration profiles was small in the presence or absence of foodintake.

The present invention is characterized by providing a pharmaceuticalcomposition for modified release which is not affected by the effects offood intake and exhibits a decreased change in AUC or Cmax, bycontrolling the releasing rate of the active ingredient.

The present invention provides:

[1] a pharmaceutical composition for modified release comprising(R)-2-(2-aminothiazol-4-yl)-4′-[2-[(2-hydroxy-2-phenylethyl)amino]ethyl]aceticacid anilide or a pharmaceutically acceptable salt thereof, and acarrier for a sustained release pharmaceutical composition, wherein adissolution rate of the drug from the composition is less than 85% after30 minutes from the beginning of a dissolution test,[2] the pharmaceutical composition for modified release of [1], whereina dissolution rate is 75% or less after 1.5 hours from the beginning ofthe dissolution test,[3] the pharmaceutical composition for modified release of [1], whereinthe dissolution rate is 75% or less after 1.5 hours from the beginningthe dissolution test, and a dissolution rate is 75% to 100% after 7hours from the beginning of the dissolution test,[4] the pharmaceutical composition for modified release of any one of[1] to [3], which is selected from the group consisting of a sustainedrelease hydrogel-forming formulation, a multi-layered formulationconsisting of a drug core and a release-controlling layer which aregeometrically arranged, a gel formulation in which a plurality of gumsis combined, an osmotic pump type formulation, a formulation utilizing aswelling polymer, a matrix formulation utilizing a water-solublepolymer, a modified release formulation with a coating membrane, and amatrix formulation utilizing an insoluble polymer,[5] a method of reducing an effect of food intake, comprising the stepof administering a pharmaceutical composition comprising(R)-2-(2-aminothiazol-4-yl)-4′-[2-[(2-hydroxy-2-phenylethyl)amino]ethyl]aceticacid anilide or a pharmaceutically acceptable salt thereof, and acarrier for a sustained release pharmaceutical composition, wherein adissolution rate of the drug from the composition is less than 85% after30 minutes from the beginning of a dissolution test,[6] the method of reducing an effect of food intake of [5], wherein adissolution rate is 75% or less after 1.5 hours from the beginning ofthe dissolution test,[7] the method of reducing an effect of food intake of [5], wherein thedissolution rate is 75% or less after 1.5 hours from the beginning thedissolution test, and a dissolution rate is 75% to 100% after 7 hoursfrom the beginning of the dissolution test, and[8] the method of reducing an effect of food intake of any one of [5] to[7], wherein the pharmaceutical composition is selected from the groupconsisting of a sustained release hydrogel-forming formulation, amulti-layered formulation consisting of a drug core and arelease-controlling layer which are geometrically arranged, a gelformulation in which a plurality of gums is combined, an osmotic pumptype formulation, a formulation utilizing a swelling polymer, a matrixformulation utilizing a water-soluble polymer, a modified releaseformulation with a coating membrane, and a matrix formulation utilizingan insoluble polymer.

As formulation techniques for reducing or avoiding the changes inpharmacokinetics such as AUC or Cmax accompanied by food intake, aformulation technique concerning a sustained-release pharmaceuticalcomposition containing tamsulosin hydrochloride is disclosed (seeJapanese Unexamined Patent Publication (Kokai) No. 2005-162736 andJapanese Unexamined Patent Publication (Kokai) No. 2005-162737). Thisformulation technique is limited to tamsulosin, and applied to aformulation containing the drug at a low dose (0.4 mg per unitformulation). This formulation enables to control the release oftamsulosin therefrom by being mainly composed of a sustained-releasebase. By contrast, the pharmaceutical composition contains the drug at ahigh dose (i.e., high content per unit formulation), and it isconsidered difficult to control the release rate of the drug from aformulation containing the sustained-release base at a low content, andtherefore, the present invention is technically quite different from theformulation disclosed in these references.

Advantageous Effects of Invention

According to the present invention, a pharmaceutical composition formodified release which has no limitations on food intake and which iscapable of reducing the changes in Cmax and AUC can be provided.

With respect to a conventional formulation, the rate of decrease of Cmaxin a fed state was 67% in comparison with that in a fasted state. Bycontrast, with respect to the pharmaceutical composition for modifiedrelease of the present invention, the rate of decrease of Cmax in a fedstate was 4% or 10% in comparison with that in a fasted state, and thisresult showed that reduction of Cmax caused by food intake could besignificantly alleviated by forming its formulation into thepharmaceutical formulation for modified release.

With respect to a conventional formulation, the rate of decrease of AUCin a fed state was 47% in comparison with that in a fasted state. Bycontrast, with respect to the pharmaceutical composition for modifiedrelease of the present invention, the rate of decrease of AUC in a fedstate was 10% or −4% in comparison with that in a fasted state, and thisresult showed that reduction of AUC caused by food intake could besignificantly alleviated by forming its formulation into thepharmaceutical formulation for modified release.

BRIEF DESCRIPTION OF DRAWINGS

FIG. 1 is a graph showing the drug release property from each of theformulations prepared in Examples 1A to 1C in Experimental Example 1.

FIG. 2 is a graph showing the drug release property from each of theformulations prepared in Examples 2A to 2D in Experimental Example 2.

FIG. 3 is a graph showing the drug release property from the formulationprepared in Example 3 in Experimental Example 3.

FIG. 4 is a graph showing the drug release property from the formulationprepared in Example 4 in Experimental Example 4.

FIG. 5 is a graph showing the drug release property from each of theformulations prepared in Examples 5A to 5C in Experimental Example 5.

FIG. 6 is a graph showing the drug release property from each of theformulations prepared in Examples 6A to 6G in Experimental Example 6.

FIG. 7 is a graph showing the drug release property from each of theformulations prepared in Examples 6H to 6N in Experimental Example 6.

FIG. 8 is a graph showing the drug release property from each of theformulations prepared in Examples 7A to 7E in Experimental Example 7.

FIG. 9 is a graph showing the drug release property from each of theformulations prepared in Examples 8A to 8C in Experimental Example 8.

FIG. 10 is a graph showing the drug release property from each of theformulations prepared in Examples 8D to 8G in Experimental Example 8.

FIG. 11 is a graph showing the relation between Cmax and the increase inheart rate from the base line in Experimental Example 9 (a dotted lineshows 95% confidence interval).

FIG. 12 is a graph showing blood concentration profiles after theadministration of the formulation of Example 1A in a fasted state orafter 30 minutes from the intake of food in Experimental Example 10.

FIG. 13 is a graph showing the blood concentration profiles after theadministration of the formulation of Example 1B in a fasted state orafter 30 minutes from the intake of food in Experimental Example 10.

DESCRIPTION OF EMBODIMENTS

The pharmaceutical composition for modified release of the presentinvention will be explained hereinafter.

The term “immediate release formulation (conventional formulation)” asused herein means a formulation in which the dissolution rate of thedrug from the formulation is 85% or more after 30 minutes from thebeginning a dissolution test, which is carried out in accordance with adissolution test (paddle method) described in the United StatesPharmacopoeia under the conditions that 900 mL of an appropriate testfluid (such as a USP buffer, pH 6.8) is used and the paddle rotationspeed is 100 rpm. Alternatively, the term means a formulation in whichthe dissolution rate of the drug from the formulation is 85% or moreafter 30 minutes from the beginning a dissolution test, which is carriedout in accordance with a dissolution test, method 2 described in theJapanese Pharmacopoeia under the conditions that 900 mL of anappropriate test fluid (such as a Mc. Ilvain buffer, pH 6.8) is used andthe paddle rotation speed is 50 rpm. Alternatively, the term means aformulation in which the dissolution rate of the drug from theformulation is 85% or more after 30 minutes from the beginning adissolution test, which is carried out in accordance with a dissolutiontest, method 2 (paddle method) described in the Japanese Pharmacopoeiaunder the conditions that 900 mL of a USP phosphate buffer (pH 6.8) isused as a test fluid and the paddle rotation speed is 200 rpm.

The term “pharmaceutical composition for modified release” as usedherein means a formulation in which the dissolution rate of the drugfrom the formulation is less than 85% after 30 minutes from thebeginning a dissolution test carried out under the above conditions, andthe drug release is controlled to the extent that the effects by foodare reduced.

The wording “the effects by food are reduced” as used herein means, forexample, a reduction by 10% or more, a reduction by 20% or more inanother embodiment, and a reduction by 30% or more in still anotherembodiment, in comparison with Cmax of a conventional formulation.Alternatively, the term means, for example, a reduction by 10% or morewith respect to the rates of decrease of Cmax and AUC in administrationafter food intake, in comparison with Cmax and AUC in administration inthe fasted state, a reduction by 20% or more in another embodiment, anda reduction by 30% or more in still another embodiment.

The rates of decrease of Cmax and AUC are calculated by the followingequations:Rd(Cmax)=[Cmax(FS)−Cmax(FI)]×100/Cmax(FS)Rd(AUC)=[AUC(FS)−AUC(FI)]×100/AUC(FS)Rd(Cmax): Rate of decrease of Cmax (%)Cmax(FS): Cmax in administration in the fasted stateCmax(FI): Cmax in administration after food intakeRd(AUC): Rate of decrease of AUC (%)AUC(FS): AUC in administration in the fasted stateAUC(FI): AUC in administration after food intake

The term “formulation in which the effects by food are reduced” as usedherein means a formulation in which the dissolution rate of the drugfrom the formulation is less than 85% after 30 minutes from thebeginning a dissolution test, which is carried out under the aboveconditions. In another embodiment, it means a formulation in which thedissolution rate of the drug from the formulation is 75% or less after1.5 hours from the beginning a dissolution test. In still anotherembodiment, it means a formulation in which the dissolution rate of thedrug from the formulation is 75% or less after 1.5 hours and 75% to 100%after 7 hours from the beginning a dissolution test.

(R)-2-(2-aminothiazol-4-yl)-4′-[2-[(2-hydroxy-2-phenylethyl)amino]ethyl]aceticacid anilide (hereinafter sometimes referred to as compound A) isrepresented by the following structural formula.

Compound A may be used in a free form which is not a salt, and may forma salt with an acid in other embodiments. Examples of such a saltinclude an acid addition salt with a mineral acid such as hydrochloricacid, hydrobromic acid, hydroiodic acid, sulfuric acid, nitric acid,phosphoric acid, or the like; and an acid addition salt with an organicacid such as formic acid, acetic acid, propionic acid, oxalic acid,malonic acid, succinic acid, fumaric acid, maleic acid, lactic acid,malic acid, citric acid, tartaric acid, carbonic acid, picric acid,methanesulfonic acid, ethanesulfonic acid, glutamic acid, or the like.

The dose of compound A may be appropriately selected in accordance withsymptom, age, sex, and the like of the patient to be treated. The dailydose of compound A for oral administration to an adult is generally 0.01to 100 mg/kg, which is administered once or divided into two to fourdoses per day.

The content of compound A per formulation is, for example, 1% by weightto 70% by weight, 5% by weight to 70% by weight in another embodiment,and 5% by weight to 50% by weight in still another embodiment. Thecontent of compound A per formulation is 1 mg to 500 mg, and 10 mg to200 mg in another embodiment.

A carrier for a sustained release pharmaceutical composition, which iscontained in the pharmaceutical composition for modified release of thepresent invention together with compound A or a pharmaceuticallyacceptable salt thereof, is not particularly limited, so long as it is acarrier, a pharmaceutical formulation, or a technique for manufacturingpharmaceutical preparations capable of achieving a specific releaserate.

Examples of such a carrier (or a pharmaceutical formulation, or atechnique for manufacturing pharmaceutical preparations) which forms thecomposition or components in the present invention include, for example,

(1) a sustained release hydrogel-forming formulation in which theformulation is almost completely gelled during the retention in thestomach and the small intestine of the upper digestive tract and thedrug can be released in the colon of the lower digestive tract,(2) a multi-layered formulation consisting of a drug core and arelease-controlling layer which are geometrically arranged,(3) a gel formulation in which a plurality of gums is combined,(4) an osmotic pump type formulation,(5) a formulation utilizing a swelling polymer,(6) a matrix formulation utilizing a water-soluble polymer,(7) a modified release formulation with a coating membrane,(8) a matrix formation utilizing an insoluble polymer, and the like, asdescribed in detail below. The compositions relating to these techniquesfor manufacturing pharmaceutical preparations, and the techniques per seare incorporated herein by reference.

Hereinafter, each embodiment of the pharmaceutical composition formodified release of the present invention will be explained in detail.Each embodiment described below is mainly explained with reference tocases using compound A as the active ingredient, but instead of compoundA, a pharmaceutically acceptable salt thereof may be used.

(1) Sustained Release Hydrogel-Forming Formulation

The sustained release hydrogel-forming formulation contains, as thecarrier for a sustained release pharmaceutical composition, an additivethat allows water to penetrate into the formulation (designated as agelling agent, a promoting agent for gelling, and a hydrophilic base,but hereinafter referred to as hydrophilic base), and a polymer whichforms a hydrogel (hereinafter referred to as hydrogel-forming polymer).

It is necessary that the hydrogel-forming polymer used in the presentinvention can control the release rate of the drug, to the extent thatthe blood concentration profile of the drug is not affected by thepresence or absence of food intake.

The molecular weight of the hydrogel-forming polymer is, for example,100,000 or more, 100,000 to 8,000,000 in another embodiment, 100,000 to5,000,000 in still another embodiment, and 100,000 to 2,000,000 in stillanother embodiment. The viscosity of the hydrogel-forming polymer is,for example, 12 mPa·s or more in a 5% aqueous solution at 25° C.; 12mPa·s or more in a 5% aqueous solution at 25° C., and 40,000 mPa·s orless in a 1% aqueous solution at 25° C. in another embodiment; 400 mPa·sor more in a 2% aqueous solution at 25° C., and 7,500 mPa·s or less in a1% aqueous solution at 25° C. in still another embodiment; and 400 mPa·sor more in a 2% aqueous solution at 25° C., and 5,500 mPa·s or less in a1% aqueous solution at 25° C. in still another embodiment.

In the pharmaceutical composition for modified release of the presentinvention, the release period of time of the drug from the formulationcan be arbitrarily controlled by adjusting the viscosity of the polymerwhich is used as the hydrogel-forming polymer.

The hydrogel-forming polymer used in the present invention is notparticularly limited, so long as the release of the drug can becontrolled to the extend that the effects of food on compound A may bereduced. Examples of the hydrogel-forming polymer include polyethyleneoxide, hypromellose, hydroxypropyl cellulose, carboxymethyl cellulosesodium, hydroxyethyl cellulose, and carboxyvinyl polymers. Examples ofthe hydrogel-forming polymer in another embodiment include polyethyleneoxide, hypromellose, and hydroxypropyl cellulose.

Examples of polyethylene oxide (hereinafter sometimes referred to asPEO) include product names, Polyox WSR-308 [average molecular weight:8,000,000, viscosity: 10,000-15,000 mPa·s (1% aqueous solution at 25°C.)], Polyox WSR-303 [average molecular weight: 7,000,000, viscosity:7,500-10,000 mPa·s (1% aqueous solution at 25° C.)], Polyox WSRCoagulant [average molecular weight: 5,000,000, viscosity: 5,500-7,500mPa·s (1% aqueous solution at 25° C.)], Polyox WSR-301 [averagemolecular weight: 4,000,000, viscosity: 1,650-5,500 mPa·s (1% aqueoussolution at 25° C.)], Polyox WSR-N-60K [average molecular weight:2,000,000, viscosity: 2,000-4,000 mPa·s (2% aqueous solution at 25°C.)], Polyox WSR-N-12K [average molecular weight: 1,000,000, viscosity:400-800 mPa·s (2% aqueous solution at 25° C.)], Polyox WSR-1105 [averagemolecular weight: 900,000, viscosity: 8,800-17,600 mPa·s (5% aqueoussolution at 25° C.)], Polyox WSR-205 [average molecular weight: 600,000,viscosity: 4,500-8,800 mPa·s (5% aqueous solution at 25° C.)], PolyoxWSR-N-750 [average molecular weight: 300,000, viscosity: 600-1200 mPa·s(5% aqueous solution at 25° C.)], Polyox WSR-N-80 [average molecularweight: 200,000, viscosity: 55-90 mPa·s (5% aqueous solution at 25°C.)], and Polyox WSR-N-10 [average molecular weight: 100,000, viscosity:12-50 mPa·s (5% aqueous solution at 25° C.)] (DOW).

Examples of hypromellose (hereinafter sometimes referred to as HPMC)include product name Metolose 90SH50000 [viscosity in a 2% aqueoussolution at 20° C.: 2,900-3,900 mPa·s], Metolose SB-4 (product name,Shin-Etsu Chemical Co., Ltd.) (viscosity in a 2% aqueous solution at 20°C.: approximately 4 mPa·S), TC-5RW (product name, Shin-Etsu ChemicalCo., Ltd.) (viscosity in a 2% aqueous solution at 20° C.: approximately6 mPa·S), TC-5S (product name, Shin-Etsu Chemical Co., Ltd.) (viscosityin a 2% aqueous solution at 20° C.: approximately 15 mPa·S), TC-5R(product name, Shin-Etsu Chemical Co., Ltd.) (viscosity in a 2% aqueoussolution at 20° C.: approximately 6 mPa·S), TC-5M (product name,Shin-Etsu Chemical Co., Ltd.) (viscosity in a 2% aqueous solution at 20°C.: approximately 4.5 mPa·S), TC-5E (product name, Shin-Etsu ChemicalCo., Ltd.) (viscosity in a 2% aqueous solution at 20° C.: approximately3 mPa·S), Metolose 60SH-50 (product name, Shin-Etsu Chemical Co., Ltd.)(viscosity in a 2% aqueous solution at 20° C.: approximately 50 mPa·s),Metolose 65SH-50 (product name, Shin-Etsu Chemical Co., Ltd.) (viscosityin a 2% aqueous solution at 20° C.: approximately 50 mPa·s), Metolose90SH-100 (product name, Shin-Etsu Chemical Co., Ltd.) (viscosity in a 2%aqueous solution at 20° C.: approximately 100 mPa·s), Metolose90SH-100SR (product name, Shin-Etsu Chemical Co., Ltd.) (viscosity in a2% aqueous solution at 20° C.: approximately 100 mPa·s), Metolose65SH-400 (product name, Shin-Etsu Chemical Co., Ltd.) (viscosity in a 2%aqueous solution at 20° C.: approximately 400 mPa·s), Metolose 90SH-400(product name, Shin-Etsu Chemical Co., Ltd.) (viscosity in a 2% aqueoussolution at 20° C.: approximately 400 mPa·s), Metolose 65SH-1500(product name, Shin-Etsu Chemical Co., Ltd.) (viscosity in a 2% aqueoussolution at 20° C.: approximately 1,500 mPa·s), Metolose 60SH-4000(product name, Shin-Etsu Chemical Co., Ltd.) (viscosity in a 2% aqueoussolution at 20° C.: approximately 4,000 mPa·s), Metolose 65SH-4000(product name, Shin-Etsu Chemical Co., Ltd.) (viscosity in a 2% aqueoussolution at 20° C.: approximately 4,000 mPa·s), Metolose 90SH-4000(product name, Shin-Etsu Chemical Co., Ltd.) (viscosity in a 2% aqueoussolution at 20° C.: approximately 4,000 mPa·s), Metolose 90SH-4000SR(product name, Shin-Etsu Chemical Co., Ltd.) (viscosity in a 2% aqueoussolution at 20° C.: approximately 4,000 mPa·s), Metolose 90SH-15000(product name, Shin-Etsu Chemical Co., Ltd.) (viscosity in a 2% aqueoussolution at 20° C.: approximately 15,000 mPa·s), Metolose 90SH-15000SR(product name, Shin-Etsu Chemical Co., Ltd.) (viscosity in a 2% aqueoussolution at 20° C.: approximately 15,000 mPa·s), and Metolose 90SH-30000(product name, Shin-Etsu Chemical Co., Ltd.) (viscosity in a 2% aqueoussolution at 20° C.: approximately 30,000 mPa·s).

Examples of hydroxypropyl cellulose (hereinafter sometimes referred toas HPC) include HPC-SSL (product name, Nippon Soda Co., Ltd.) (viscosityin a 2% aqueous solution at 20° C.: 2.0-2.9 mPa·S), HPC-SL (productname, Nippon Soda Co., Ltd.) (viscosity in a 2% aqueous solution at 20°C.: 3.0-5.9 mPa·S), HPC-L (product name, Nippon Soda Co., Ltd.)(viscosity in a 2% aqueous solution at 20° C.: 6.0-10.0 mPa·S), HPC-M(product name, Nippon Soda Co., Ltd.) (viscosity in a 2% aqueoussolution at 20° C.: 150-400 mPa·S), and HPC-H (product name, Nippon SodaCo., Ltd.) (viscosity in a 2% aqueous solution at 20° C.: 1,000-4,000mPa·S).

Examples of methylcellulose (hereinafter sometimes referred to as MC)include Metolose SM15 (product name, Shin-Etsu Chemical Co., Ltd.)(viscosity in a 2% aqueous solution at 20° C.: approximately 15 mPa·S),Metolose SM25 (product name, Shin-Etsu Chemical Co., Ltd.) (viscosity ina 2% aqueous solution at 20° C.: approximately 25 mPa·S), Metolose SM100(product name, Shin-Etsu Chemical Co., Ltd.) (viscosity in a 2% aqueoussolution at 20° C.: approximately 100 mPa·S), Metolose SM400 (productname, Shin-Etsu Chemical Co., Ltd.) (viscosity in a 2% aqueous solutionat 20° C.: approximately 400 mPa·S), Metolose SM1500 (product name,Shin-Etsu Chemical Co., Ltd.) (viscosity in a 2% aqueous solution at 20°C.: approximately 1,500 mPa·S), and Metolose SM4000 (product name,Shin-Etsu Chemical Co., Ltd.) (viscosity in a 2% aqueous solution at 20°C.: approximately 4,000 mPa·S).

Examples of carboxymethyl cellulose sodium (hereinafter sometimesreferred to as CMCNa) include product names, Sunrose F-30MC [viscosity:250-350 mPa·s (1% aqueous solution at 25° C.)], Sunrose F-150MC [averagemolecular weight: 200,000, viscosity: 1,200-1,800 mPa·s (1% aqueoussolution at 25° C.)], Sunrose F-600MC [viscosity: 6,000-8,000 mPa·s (1%aqueous solution at 25° C.)], Sunrose F-1000MC [average molecularweight: 420,000, viscosity: 8,000-12,000 mPa·s (the same)], SunroseF-1400MC [viscosity: 12,000-15,000 mPa·s (1% aqueous solution at 25°C.)], and Sunrose F-300MC [average molecular weight: 300,000, viscosity:2,500-3,000 mPa·s (the same)](Nippon Paper Chemicals Co., Ltd.).

Examples of hydroxyethyl cellulose (hereinafter sometimes referred to asHEC) include product names, HEC DAICEL SE850 [average molecular weight:1,480,000, viscosity: 2,400-3,000 mPa·s (1% aqueous solution at 25°C.)], and HEC DAICEL SE900 [average molecular weight: 1,560,000,viscosity: 4,000-5,000 mPa·s (1% aqueous solution at 25° C.)](Daicelchemical Industries, Ltd.).

Examples of carboxyvinyl polymers include Carbopol 71G (viscosity:4,000-11,000 mPa·s), Carbopol 971P (viscosity: 4,000-11,000 mPa·s),Carbopol 981 (viscosity: 4,000-10,000 mPa·s), Carbopol 941 (viscosity:4,000-10,000 mPa·s), Carbopol 934 (viscosity: 30,500-39,400 mPa·s), andCarbopol 934P (viscosity: 29,400-39,400 mPa·s) (B.F. Goodrich Chemical).

These hydrogel-forming polymers may be used alone, or as an appropriatecombination of two or more thereof. A combination of different lots maybe used.

The content of the hydrogel-forming polymer is not particularly limited,so long as it is an amount to the extent that the blood concentrationprofile of the drug is not affected by the presence or absence of foodintake. The content of the hydrogel-forming polymer is, for example, 1%by weight to 70% by weight with respect to the total weight of theformulation, and 3% by weight to 70% by weight in another embodiment.The content of the hydrogel-forming polymer is 5% by weight to 70% byweight with respect to the total weight of the formulation, 10% byweight to 60% by weight in another embodiment, and 10% by weight to 40%by weight in still another embodiment. The content of thehydrogel-forming polymer is 0.1% by weight to 1,000% by weight withrespect to the weight of the drug, 1% by weight to 500% by weight inanother embodiment, and 5% by weight to 300% by weight in still anotherembodiment.

A polymer of which the viscosity (before mixing) is beyond the specificrange can be used as an appropriate combination with one or more otherpolymers, in case that the mixture obtained by mixing these pluralpolymers has a viscosity (as measured before the use) within thespecific range.

In the additive which ensures penetration of water into thepharmaceutical composition of the present invention (hydrophilic base),the amount of water necessary to dissolve 1 g of the hydrophilic base at20±5° C. is 10 mL or less, 6 mL or less in another embodiment, 5 mL orless in still another embodiment, and 4 mL or less in still anotherembodiment. When the hydrophilic base has a high solubility to water,the effect that allows water to penetrate into the formulation is high.

Examples of the hydrophilic base include water-soluble polymers, such aspolyethylene glycol [PEG: for example, product names PEG 400, PEG 1500,PEG 4000, PEG 6000, and PEG 20000 (NOF Corporation)], polyvinylpyrrolidone (PVP: for example, product name PVP K30 (BASF), and thelike; sugar alcohols, such as D-mannitol, D-sorbitol, xylitol, and thelike; saccharides, such as lactose, sucrose, anhydrous maltose,D-fructose, dextran (for example, Dextran 40), glucose, and the like;surfactants, such as polyoxyethylene hydrogenated castor oil [HCO: forexample, Cremophor RH40 (BASF), HCO-40, HCO-60 (Nikko Chemicals)],polyoxyethylene polyoxypropylene glycol [for example, Pluronic F68(ADEKA Corporation and the like)], polyoxyethylene sorbitan higher fattyacid esters [Tween: for example, Tween 80 (Kanto Chemical)], and thelike; salts, such as sodium chloride, magnesium chloride, and the like;organic acids, such as citric acid, tartaric acid, and the like; aminoacids, such as glycine, β-alanine, lysine hydrochloride, and the like;and aminosaccharides, such as meglumine and the like.

As another embodiment, PEG, PVP, D-mannitol, D-sorbitol, xylitol,lactose, sucrose, anhydrous maltose, D-fructose, dextran, glucose,polyoxyethylene polyoxypropylene glycol, sodium chloride, magnesiumchloride, citric acid, tartaric acid, glycine, β-alanine, lysinehydrochloride, or meglumine may be used. As still another embodiment,PEG, PVP, D-mannitol, lactose, sucrose, sodium chloride, polyoxyethylenepolyoxypropylene glycol, or the like may be used.

These hydrophilic bases may be used alone, or as an appropriatecombination of two or more thereof.

The content of the hydrophilic base is not particularly limited, so longas it is an amount capable of controlling the release of the drug to theextent that the release of the drug is not affected by food. The contentof the hydrophilic base is, for example, 5% by weight to 75% by weight,5% by weight to 70% by weight in another embodiment, and 20% by weightto 60% by weight in still another embodiment.

The sustained release hydrogel-forming formulation, as an embodiment ofthe pharmaceutical composition for modified release of the presentinvention, may be prepared as various dosage forms, which include, forexample, formulations for oral administration such as tablets, capsules(including microcapsules), granules, and powder, and formulations forparenteral administration such as suppositories (for example, rectalsuppositories or vaginal suppositories). These formulations may besafely administered orally or parenterally. Formulations for oraladministration such as tablets, capsules, and granules may be selectedin another embodiment.

Hereinafter, various pharmaceutical additives which may be used in thesustained release hydrogel-forming formulation, as an embodiment of thepharmaceutical composition for modified release of the presentinvention, and various methods for preparing the sustained releasehydrogel-forming formulation will be explained, but these explanationsare not particularly limited to the sustained release hydrogel-formingformulation, and can be applied to formulations other than the sustainedrelease hydrogel-forming formulation.

The pharmaceutical composition for modified release of the presentinvention may be prepared by mixing the drug, the hydrogel-formingpolymers, and the hydrophilic base, and forming the mixture into apredetermined shape. The mixing and forming may be carried out inaccordance with conventional methods widely used in the technical fieldfor formulation. A pharmaceutically acceptable carrier may be used inthe mixing and/or forming, if desired.

In the preparation of the pharmaceutical composition for modifiedrelease of the present invention, further various pharmaceuticaladditives may be used, if desired. Such pharmaceutical additives are notparticularly limited, so long as they are pharmaceutically acceptable.Examples of the pharmaceutical additives include various organic orinorganic carrier substances which are widely used as formulationmaterials, such as fillers, lubricants, binders, and disintegratingagents. Other formulation additives such as preservatives, antioxidants,stabilizers, film coating agents, coloring agents, and sweeteners may beused, if desired.

Examples of the fillers include lactose, sucrose, D-mannitol,D-sorbitol, starch, gelatinized starch, dextrin, crystalline cellulose,low substituted hydroxypropyl cellulose, carboxymethyl cellulose sodium,gum arabic, dextrin, pullulan, light anhydrous silicic acid, syntheticaluminum silicate, magnesium aluminate metasilicate, and the like.

Examples of the lubricants include magnesium stearate, calcium stearate,talc, colloidal silica, and the like.

Examples of the binders include gelatinized starch, sucrose, gelatin,gum arabic, methylcellulose, carboxymethyl cellulose, carboxymethylcellulose sodium, crystalline cellulose, sucrose, D-mannitol, trehalose,dextrin, pullulan, hydroxypropyl cellulose, hypromellose,polyvinylpyrrolidone, and the like.

Examples of the disintegrating agents include lactose, sucrose, starch,carboxymethyl cellulose, carboxymethyl cellulose calcium, croscarmellosesodium, carboxymethyl starch sodium, light anhydrous silicic acid, lowsubstituted hydroxypropylcellulose, and the like.

Examples of the preservatives include p-hydroxybenzoate esters,chlorobutanol, benzyl alcohol, phenethyl alcohol, dehydroacetic acid,sorbic acid, and the like.

Examples of the antioxidants include butylated hydroxytoluene (BHT),propyl gallate (PG), butylhydroxyanisol (BHA), ascorbic acid, sodiumascorbate, erythorbic acid, sodium nitrite, sodium bisulfite, sodiumpyrosulfite, citric acid, and edetate sodium; BHT, PG, and sodiumascorbate in another embodiment; and BHT in still another embodiment.

Examples of the stabilizers include yellow ferric oxide, red ferricoxide, black iron oxide, and the like.

Examples of the film coating agents include pharmaceuticallycommonly-used bases, such as water-soluble polymers, plasticizers, andinorganic substances, or a combination thereof.

Examples of the coloring agents include water-soluble edible tarpigments (examples: edible pigments such as food red No. 2, food red No.3, food yellow No: 4, food yellow No. 5, food blue No. 1, and food blueNo. 2), water-insoluble lake pigments (examples: aluminum salts of theabove water-soluble edible tar pigments), natural pigments (examples:β-carotene, chlorophyll, and colcothar), and the like.

Examples of the sweeteners include saccharin sodium, dipotassiumglycyrrhizinate, aspartame, stevia, and the like.

These carriers or formulation additives may be used alone, or as anappropriate combination of two or more thereof. With respect to thecontents thereof, they may be used in appropriate amounts.

Hereinafter, the process of manufacturing the pharmaceutical compositionfor modified release of the present invention will be explained, thepresent invention is not limited to the following particularembodiments.

The pharmaceutical composition for modified release of the presentinvention may be prepared by known methods per se, such as drygranulation, wet granulation, fluidized bed granulation, intermittentgranulation, agitation granulation, or the like.

As a method of de-lumping or pulverizing the drug, conventional crushingor pulverizing methods may be applied, for example, using an impact mill(Hosokawa Micron Corporation; Fine Impact Mill), a dry & wet mill(Powrex Corporation: Comil), or a cutting mill granulator (DaltonCorporation; Power Mill).

As a method of pulverizing the hydrophilic base, the hydrogel-formingpolymer, or the formulation additives, conventional pulverizing methodsmay be applied, for example, using an impact mill (Hosokawa MicronCorporation; Fine Impact Mill or Sample Mill) or a jet mill (HorkosCorp; Jet Mill).

As a method of granulating the drug, conventional granulation methodsmay be used. Examples of such methods include a fluidized bedgranulation method, an intermittent granulation method, an agitationgranulation method, a high-speed agitation granulation method, atumbling fluidized bed granulation method, an extrusion granulationmethod, a pulverization granulation method, a dry granulation method,and the like. In another embodiment, examples thereof include afluidized bed granulation method, an intermittent granulation method, anagitation granulation method, a high-speed agitation granulation method,a tumbling fluidized bed granulation method, and a dry granulationmethod, and any method capable of granulating the drug may be used.Examples of a granulator include a fluidized bed granulator (forexample, Flow Coater; Freund Corporation, or GPCG; Glatt GmbH), agranulation and coating apparatus equipped with a horizontal rotatingdisc having a flat powder contact portion [for example, a centrifugalfluidizing granulator (for example, CF granulator; Freund Corporation)],a granulation and coating apparatus having a rotating disk with a flatsurface placed at the bottom of a fluidized bed and having an aerationportion (for example, Spiralflow, or Flowcoater with a rotor container;Freund Corporation), and a dry granulator in which material powder isdirectly compressed, molded, crushed, and sieved (for example, RollerCompactor; Freund Corporation).

In the dry granulation, for example, the drug, the hydrogel-formingpolymer, the hydrophilic base, and additives such as a filler may becompression-molded using a dry granulator, and then, may be crushed andsieved to obtain granulated products having a desired size.

In the wet granulation, for example, while the drug, thehydrogel-forming polymer, the hydrophilic base, and additives such as afiller is fluidized, an appropriate amount of water or a liquidcontaining the hydrophilic base and the binder may be sprayed. Theliquid containing the hydrophilic base may be prepared by dissolving ordispersing the essential component in a solvent such as water, ethanol,methanol, or the like. These solvents may be used as an appropriatemixture thereof.

The amount of water used in the granulation is not particularly limited,so long as the binder or formulation additives may be uniformlydissolved and/or suspended (dispersed) in the water. When thehydrophilic base is used in the solid form, the amount of water is notparticularly limited, so long as the hydrogel-forming polymer can begranulated.

When the hydrophilic base is used in the liquid form, the amount ofwater to the hydrogel-forming polymer is generally 10% by weight orless, 8% by weight or less in another embodiment, and 5% by weight orless in still another embodiment. A method of adding water in thegranulation is not particularly limited, so long as a nonuniform mixtureconsisting of untreated powder and aggregates, which are generallypowdery, is not generated. Examples thereof include a continuous spraymethod in which water is continuously added, an intermittent spraymethod in which a dry step (and a shaking step, if desired) is carriedout during the granulation step, and the like.

The addition rate of water in the granulation is not particularlylimited, so long as a nonuniform mixture consisting of untreated powderand aggregates, which are generally powdery, is not generated. In thefluidized bed granulation, the addition rate of water to thehydrogel-forming polymer is generally 0.1% by weight/min. to 1% byweight/min., 0.2% by weight/min. to 0.8% by weight/min. in anotherembodiment, and 0.4% by weight/min. to 0.6% by weight/min. in stillanother embodiment.

The temperature of the powder in the granulation is not particularlylimited, so long as it does not induce thermal denaturation of thehydrogel-forming polymer. The temperature is, for example, 20° C. to themelting point (62° C. to 67° C.) of the hydrogel-forming polymer, 20° C.to 50° C. in another embodiment, 20° C. to 35° C. in still anotherembodiment, and 25° C. to 30° C. in still another embodiment.

The concentration of the binder liquid as a solid content which may beused in the granulation is, for example, 1% to 20% as a formulationamount. The binder is not particularly limited, so long as it ispharmaceutically acceptable.

The binder may be added in the solid form to a granulator, and then,water may be sprayed as the binder liquid. Alternatively, the binder maybe dissolved in water, and then, the resulting binder liquid may besprayed.

An appropriate spray rate of the binder liquid varies according to aproduction method to be applied or its production scale. In a 1-kg scaleproduction by the fluidized bed granulation, the spray rate is 2 g/min.to 20 g/min., and 5 g/min. to 15 g/min. in another embodiment.

An appropriate temperature of the product in the granulation is 15° C.to 50° C., and 15° C. to 40° C. in another embodiment.

The resulting granulated products may be, for example, dried or heated.

In the drying step, an apparatus and a method are not particularlylimited, so long as the granulated products can be dried. Examples of anapparatus for drying include a fluidized bed granulator (for example,Flow Coater; Freund Corporation, or GPCG; Glatt GmbH), a granulation andcoating apparatus equipped with a horizontal rotating disc having a flatpowder contact portion [for example, a centrifugal fluidizing granulator(for example, CF granulator; Freund Corporation)], a granulation andcoating apparatus having a rotating disk with a flat surface placed atthe bottom of a fluidized bed and having an aeration portion (forexample, Spiralflow, or Flowcoater with a rotor container; FreundCorporation), and the like. The conditions for drying are notparticularly limited, so long as the granulated products may begenerally dried in the fluidized bed. The drying of the granulatedproducts will be almost completed, for example, under the conditions inwhich the dry inlet air temperature is 50° C. and the drying is carriedout until the temperature of the granulated products becomes 40° C. and,in another embodiment, under the conditions in which the dry inlet airtemperature is 40° C. and the drying is carried out until thetemperature of the granulated products becomes 30° C. As the dryingmethod, forced-air drying or drying under reduced pressure may be used.

The granulated products may be sieved.

In the sieving step, an apparatus and a method are not particularlylimited, so long as the granulated products can be sieved. Examples ofan apparatus for sieving include a screen, a dry & wet mill (PowrexCorporation: Comil), a cutting mill granulator (Dalton Corporation;Power Mill), and the like. The conditions for sieving are notparticularly limited, so long as the granulated products may begenerally sieved to obtain particles having a desired size.

Examples of tabletting include a direct tabletting method in which thedrug, the hydrophilic base, and the hydrogel-forming polymer are mixedwith an appropriate additive(s), and the mixture is compression-moldedto obtain tablets; a method in which a composition obtained by a wetgranulation (the granulation is carried out by spraying a mixture of thedrug, the hydrophilic base, the hydrogel-forming polymer, and additiveswith a binder liquid) or a melting granulation (the granulation iscarried out by heating a mixture of the drug, the hydrophilic base, thehydrogel-forming polymer, and an appropriate low-melting substance) isformed into tablets; and the like.

A rotary tabletting machine, a single punch tabletting machine, and thelike may be used as a tabletting machine. A method as well as anapparatus is not particularly limited, so long as a compression-moldedproduct (preferably tablets) can be pharmaceutically produced.

After the tabletting, the obtained tablets may be dried. The initialwater content of the tablet is, for example, 2% by weight/tablet orless, 1.5% by weight/tablet or less in another embodiment, and 0.9% byweight/tablet or less in still another embodiment.

After the tabletting, the obtained tablets may be film coated using apan coating machine at an amount of 1% by weight to 5% by weight pertablet.

(2) Multi-Layered Formulation Consisting of Drug Core andRelease-Controlling Layer which are Geometrically Arranged

A multilayered formulation, an embodiment of the pharmaceuticalcomposition for modified release according to the present invention, maybe a two-layered or three-layered formulation for modified release,characterized by consisting of a drug-containing layer and arelease-controlling layer, and consisting of:

a) the first layer (layer 1) which is prepared by compressing a mixtureor granules containing 5 to 90 W/W % (preferably 10 to 85 W/W %) of awater-soluble polymer in this layer, and has a property of being swollenby contact with environmental fluids,

b) the second layer (layer 2) comprising compound A, a water-solublepolymer, and other filler(s), which is adjacent to the first layer, hasa property suitable to compression-molding, and is designed to releasethe physiologically active substance within a predetermined period oftime, andc) the third layer (layer 3) (which may be optionally adjacent to thelayer 2) which contains a water-soluble polymer capable of beinggenerally gelled and/or swollen followed by optionally beingdisintegrated, and has a property of controlling the release of compoundA from the layer 2. The “environmental fluids” include, for example, anaqueous solution as used in a dissolution test, as well as body fluidssuch as blood or gastrointestinal fluids.

Techniques for such a multilayered formulation which may be used in thepharmaceutical composition for modified release according to the presentinvention are disclosed in, for example, U.S. Pat. No. 4,839,177, U.S.Pat. No. 5,422,123, U.S. Pat. No. 5,780,057, U.S. Pat. No. 6,149,940,Japanese Patent Publication (Kokai) No. 2005-162736, and Japanese PatentPublication (Kokai) No. 2005-162737, the contents of which areincorporated herein by reference. As disclosed in U.S. Pat. No.4,839,177 and U.S. Pat. No. 5,422,123, the multilayered formulation ischaracterized in that a release rate of the drug from the pharmaceuticalformulation is controlled by sandwiching the layer 2 containing the drugbetween the layer 1 and the layer 3 in which the drug is not containedor is optionally contained. Further, as disclosed in U.S. Pat. No.5,780,057 and U.S. Pat. No. 6,149,940, it is known that when themultilayered formulation is brought into contact with body fluids, atleast one of the layer 1 and the layer 3 are rapidly swollen followed bythe layer 2 is swollen, that is, the volume of the formulation issignificantly increased, and as a result, the formulation remains in thestomach for a longer period of time, and almost all of the activesubstance contained therein is released and absorbed at the uppergastrointestinal tract in a controlled manner.

The layer 1 and the layer 3 may have the same composition and the samefunctional properties, or may have different compositions and differentfunctional properties. When the layer 1 and the layer 3 have the samecomposition and functional properties, the amounts and thicknesses ofthe layers 1 and 3 which sandwich the layer 2 may be changed. At leastone of the layers 1 and 3 acts as a barrier for the release of theactive substance, that is, it is impermeable enough for compound Acontained in the layer 2 not to be released or diffused therefrom.Further, at least one of the layers 1 and 3 can be rapidly swollen, thatis, the volume thereof is rapidly increased. The layer 3 may optionallycontain the drug so that a drug release which is different from thatreleased from the layer 2 can be supplementally added to thepharmaceutical formulation.

The water-soluble polymers used in the layer 1, the layer 3, and thelayer 2 are not particularly limited, so long as they arepharmaceutically acceptable and biocompatible. Such water-solublepolymers may be gradually dissolved and/or gelled in an aqueous liquid,and/or may be gelled rapidly or at a different rate and then optionallydisintegrated. Examples of the water-soluble polymers include, forexample, hydroxymethyl cellulose, hydroxyethyl cellulose, hypromellosehaving a molecular weight of 1,000 to 4,000,000, hydroxypropyl cellulosehaving a molecular weight of 2,000 to 2,000,000, carboxyvinyl polymers,chitosans, mannans, galactomannans, xanthans, carageenans, amylose,alginic acid, salts and derivatives thereof, pectin, acrylates,methacrylates, acrylate/methacrylate copolymers, polyacid anhydrides,polyamino acids, poly(methylvinyl ether/maleic anhydride) polymers,polyvinyl alcohols, glucans, scleroglucans, carboxymethyl cellulose andderivatives thereof, ethyl cellulose, methyl cellulose, or conventionalwater-soluble cellulose derivatives. Hypromellose having a molecularweight of 3,000 to 2,000,000 is preferable. The content of thewater-soluble polymer in the layer 1 or the layer 3 is generally 5 to 90W/W %, preferably 10 to 85 W/W %, more preferably 20 to 80 W/W %, withrespect to the weight of each layer. The content of the water-solublepolymer in the layer 2 is generally 5 to 90 W/W %, preferably 10 to 85W/W %, to the weight of the layer.

In the process for preparing the layer 1 and the layer 3, awater-soluble filler which promotes the degree of wetness of the layersmay be used, to rapidly increase the volume of the multilayerdformulation containing the above water-soluble polymer. Thewater-soluble filler may be preferably selected from a group of fillershaving an extremely rapid disintegrability, such as crosslinkedpolyvinylpyrrolidone, hydroxypropyl cellulose or hypromellose having alow or medium molecular weight, crosslinked carboxymethyl cellulosesodium, carboxymethyl starch or salts thereof, divinylbenzene/potassiummethacrylate copolymers, or the like.

The content of the filler is 1 to 90 W/W % or less, preferably 5 to 50W/W % of each layer.

If desired, a surfactant (anionic, cationic, or nonionic surfactants)may be further used to improve the degree of wetness. As a result,tablets and environmental fluids may conform with each other morerapidly, and the tablets, particularly the gel-forming layer, may begelled more rapidly. Examples of the surfactant include, for example,sodium laurylsulfate, sodium ricinolate, sodium tetradecylsulfonate,sodium dioctylsulfosuccinate, cetomagrogol, poloxamer, glycerolmonostearate, polysorbate, sorbitan monolaurate, lecithins, or otherpharmaceutically acceptable surfactants.

If desired, another substance which modifies hydration may be furtherused. Such a substance may be selected from, for example, mannitol,lactose, starches derived from various organs, sorbitol, xylitol,microcrystalline cellulose, and/or a diluent capable of generallypromoting a penetration of water or an aqueous liquid into apharmaceutical composition; or a hydrophobic diluent to retard apenetration of water or an aqueous liquid into a pharmaceuticalformulation, such as ethyl cellulose, glycerol monostearate, palmitate,or hydrogenated or non-hydrogenated vegetable oils (for example,hydrogenated castor oil, wax, monoglyceride, diglyceride, ortriglyceride). It is preferable to select ethyl cellulose orhydrogenated vegetable oils as the hydrophobic diluent.

The content of the hydrophobic diluent in the layer 1 or the layer 3 isgenerally 1 to 60 W/W %, preferably 5 to 40 W/W %, more preferably 10 to30 W/W %, with respect to the weight of each layer.

To control the release rate of compound A from the pharmaceuticalformulation, microcrystalline or a water-soluble base, such as dextrose,sucrose, fructose, maltose, xylitol, citric acid, lactose, mannitol, orthe like, may be used in the layer 2, if desired.

The content of microcrystalline and/or the water-soluble base in thelayer 2 is generally 5 to 90 W/W %, preferably 10 to 80 W/W %, morepreferably 20 to 70 W/W %, with respect to the weight of the layer.

The multilayered formulation of the present invention may contain, forexample, a lubricant, such as magnesium stearate, talc, stearic acid,glycerol monostearate, polyoxyethylene glycol having a molecular weightof 400 to 7,000,000, hydrogenated castor oil, glycerol behenate,monoglyceride, diglyceride, triglyceride, or the like, a fluidizingagent such as colloidal silica or other silica, a binder, a buffer, anabsorbing agent, or other pharmaceutically acceptable additives.

The multilayered formulation of the present invention may bemanufactured, for example, by mixing powder and/or granules by a knownmanufacturing technique per se, and forming the mixture into tablets bycompression. A two-layered or three-layered pharmaceutical formulation,such as a tablet, may be manufactured by a known method per se. Themultilayered formulation of the present invention may be manufactured,for example, by using a rotary press capable of manufacturingmultilayered tablets. It is preferable that a tabletting pressure isgenerally 7 to 50 kN. When the tablets are manufactured on a smallscale, a mortar and pestle may be used to prepare powder and/orgranules, and then, an oil press tabletting machine may be used tomanufacture two-layered or three-layered tablets. The thickness of eachlayer of the formulation may vary according to the content of the activesubstance, and is preferably 0.2 to 8 mm, more preferably 1 to 4 mm. Inthe formulation of the present invention, for example, a coating layerwith a macromolecular material may be applied to the pharmaceuticalcomposition. Such a coating may be applied by using an organic oraqueous solution, in accordance with a known method per se.

When the multilayered formulation of the present invention is broughtinto contact with gastric juices in the gastrointestinal tract and/orliquids, the volume thereof is rapidly increased. This increase involume may be limited in a single layer or several layers of theformulation. Such a formulation may be in a form of a tablet, smalltablets, or a gelatin capsule consisting of small tablets. Further, atleast two small tablets may be combined in the same formulation, and maybe packed in, for example, a wafer capsule or a gelatin capsule. Whenthe formulation consists of small tablets, each small tablet may have adifferent composition or the same composition.

(3) Gel Formulation in which a Plurality of Gums is Combined

A gel formulation in which a plurality of gums is combined, anembodiment of the pharmaceutical composition for modified releaseaccording to the present invention, is characterized by comprising atleast compound A and a gum base. The gum base as used herein means asustained release filler comprising a homopolysaccharide which can forma crosslinkage with a heteropolysaccharide gum when exposed to theheteropolysaccharide gum and environmental fluids (such as body fluids,an aqueous solution for an in vitro dissolution test, or the like). Thesustained release filler may further comprise calcium sulfate and/or awater-soluble base. The gel formulation may further contain a commonlyused filler.

Techniques for obtaining the gel formulation in which a plurality ofgums is combined, which may be used in the pharmaceutical compositionfor modified release according to the present invention, are disclosedin, for example, U.S. Pat. No. 4,994,276, U.S. Pat. No. 5,128,143, U.S.Pat. No. 5,135,757, and Japanese Patent No. 2832248. As disclosedtherein, it is known that a heterogeneously dispersed filler comprisinga combination of a heteropolysaccharide and a homopolysaccharideexhibiting a synergistic effect, such as a combination of two or morepolysaccharide gums, has a viscosity higher than that of any single gum,and can cause a rapid hydration, and thus a harder gel is generated morerapidly. The contents of the above patent references are incorporatedherein by reference.

The heteropolysaccharide as used herein is defined as a water-solublepolysaccharide containing two or more sugar units. Theheteropolysaccharide is not particularly limited, so long as it has abranched-chain or spiral configuration, and has an excellent waterabsorbing property and a high viscosity improving property. As theheteropolysaccharide, for example, xanthan gum or derivatives thereof(such as deacylated xanthan gum), carboxymethyl ether, or propyleneglycol ester are preferable, and xanthan gum having a high molecularweight (>10⁶) is more preferable.

The homopolysaccharide as used herein is not particularly limited, solong as it is a polysaccharide consisting of mannose and galactose, andcan form a crosslinkage with a heteropolysaccharide. Locust bean gumhaving a high ratio of mannose to galactose is more preferable thanother galactomannans such as guar or hydroxypropyl guar.

Other naturally-occurring polysaccharide gums may be used in the presentinvention. Examples of such polysaccharides include, for example,alginic acid derivatives, carrageenan, tragacanth gum, gum arabic,karaya gum, polyethylene glycol esters of these gums, chitin, chitosan,mucopolysaccharide, konjak, starch, substituted starch, starch fragment,dextrin, British gum having a molecular weight of approximately 10,000Da, dextran, or the like. The starch may be used in an unmodified form,for example, an ungelled starch such as potato, rice, banana, or thelike, or a semisynthetic or gelled starch.

As a combination of the heteropolysaccharide and the homopolysaccharide,the combination of xanthan gum and locust bean gum is particularlypreferable. The content ratio of the heteropolysaccharide and thehomopolysaccharide is not particularly limited, so long as it is anamount effective in enhancing a desired gel strength. Such a ratio(heteropolysaccharide gum: homopolysaccharide gum) is approximately 3:1to approximately 1:3, preferably approximately 1:1.

The water-soluble cationic crosslinking agent as used herein is notparticularly limited, so long as it is a pharmaceutically acceptablemonovalent or polyvalent metal cation. As the binder, for example,calcium sulfate or the like may be used.

The water-soluble base as used herein is not particularly limited, solong as it is pharmaceutically acceptable. Examples of the water-solublebase include, for example, dextrose, sucrose, fructose, maltose,xylitol, citric acid, or the like.

The gel formulation in which a plurality of gums is combined of thepresent invention may be manufactured, for example, in apharmaceutically acceptable form for oral administration such as atablet or the like. In an embodiment, (1) a heteropolysaccharide gum,and a homopolysaccharide which can form a crosslinkage with theheteropolysaccharide gum when exposed to environmental fluids are mixedtogether under the dry condition with a pharmaceutically acceptablewater-soluble base in a desired ratio, (2) the resulting mixture issubject to a wet granulation, (3) the granules are dried, (4) the driedgranules are pulverized to obtain a sustained release filler having adesired particle size, (5) the resulting sustained release filler isgranulated together with compound A, (6) the resulting granules aredried, (7) a conventional filler, such as a lubricant or the like, isadded thereto, and (8) the resulting mixture is formed by compressioninto, for example, tablets. In another embodiment, a mixture of thesustained release filler and compound A may be granulated, together withan a solution of a hydrophobic substance (such as ethyl cellulose or thelike) in an amount sufficient to retard the hydration of the filler(i.e., gums) without the destruction thereof, and then a conventionalfiller such as a lubricant is added thereto, and the resulting mixtureis formed by compression into, for example, tablets.

In the wet granulation, predetermined amounts of theheteropolysaccharide gum, the homopolysaccharide gum, the cationiccrosslinking agent, and the water-soluble base are homogeneously mixed;and then, a wetting agent, such as water, propylene glycol, glycerol,alcohol, or the like, is added thereto to prepare a wet aggregate; andthe resulting wet aggregate is dried, and pulverized using aconventional apparatus to prepare granules having a predeterminedparticle size.

As the lubricant, for example, stearic acid or the like may be used. Themixing of the hydrophobic substance with the sustained release fillermay be carried out, for example, by using a liquid in which thehydrophobic substance is dissolved and/or dispersed in an organicsolvent, and further granulating the above-mentioned granules togetherwith the liquid.

Examples of the hydrophobic substance include, for example, apharmaceutical acceptable hydrophobic cellulose, such as ethyl celluloseor the like.

A combination and a mixing ratio of each component are not particularlylimited. In a preferred embodiment, approximately 5 to 60 W/W % ofxanthan gum (as the heteropolysaccharide) and locust bean gum (as thehomopolysaccharide) (xanthan gum: locust bean gum=approximately 1:1)with respect to the total weight of the pharmaceutical formulation maybe contained, and approximately 10 W/W % or less of calcium sulfate (asthe water-soluble cationic crosslinking agent) and approximately 30 to70 W/W % of dextrose (as an inert diluent) may be further contained. Tocontrol the release rate, the hydrophobic substance may be added, and,for example, approximately 5 to 10 W/W % of ethyl cellulose may becontained.

(4) Osmotic Pump Type Formulation

Osmotic pump type formulations utilize osmotic pressure to generate adriving force for imbibing fluid into a formulation, by a semipermeablemembrane that permits free diffusion of fluid but not a drug or anosmoagent. The osmotic systems are characterized in that the actionthereof is pH-independent, and a drug can be sustainedly released at aconstant rate for a long time, even as the formulation transits thegastrointestinal tract and encounters environments having different pHvalues.

Such osmotic pump type formulations are reported in Santus and Baker,“Osmotic drug delivery: a review of the patent literature”, Journal ofControlled Release, 35, p. 1-21, (1995). Further, osmotic pump typeformulations are described in U.S. Pat. Nos. 3,845,770, 3,916,899,3,995,631, 4,008,719, 4,111,202, 4,160,020, 4,327,725, 4,519,801,4,578,075, 4,681,583, 5,019,397, and 5,156,850, the contents of whichare incorporated herein by reference.

In the osmotic pump type formulation of the present invention, abilayered compressed core consisting of a drug layer containing compoundA, and a push layer, is coated with a semipermeable membrane thatpermits water or outer fluid but not a drug, an osmoagent, anosmopolymer, or the like. The semipermeable membrane is provided with atleast one drug delivery orifice for connecting the inside of theformulation with the exterior environment. Therefore, after the osmoticpump type formulation is orally administered, fluid such as watertransits the semipermeable membrane, and penetrates into the inside ofthe formulation. As a result, an osmotic action is generated, andcompound A is sustainedly released through the drug delivery orifice(s)at a constant rate for a long time.

The drug layer contains compound A, as a mixture with a pharmaceuticallyacceptable additive(s).

The push layer contains one or more osmotic active components, but doesnot contain compound A, as described in detail below. Typical osmoticactive component(s) contained in the push layer may be composed of anosmoagent and one or more osmopolymers. The osmopolymer as used hereinmeans a polymer which has relatively a large molecular weight and swellswhen fluid is imbibed, to release compound A through the drug deliveryorifice(s).

The semipermeable membrane used is not particularly limited, so long asit is permeable to the passage of an external fluid, such as water andbiological fluids, and substantially impermeable to the passage ofcompound A, an osmoagent, an osmopolymer, and the like. Such asemipermeable membrane is essentially nonerodible, and insoluble in aliving body.

As polymers for forming the semipermeable membrane, for example,semipermeable homopolymers, semipermeable copolymers, and the like maybe used. As materials for such polymers, cellulosic polymers, such ascellulose esters, cellulose ethers, cellulose ester-ethers, and thelike, may be used. The cellulosic polymers have a degree of substitution(DS) of anhydroglucose units of more than 0 and 3 or less. The degree ofsubstitution (DS) means the average number of hydroxyl groups originallypresent on the anhydroglucose units that are replaced by a substitutinggroup or converted into another group. The anhydroglucose unit can bepartially or completely substituted with groups, such as acyl, alkanol,alkenoyl, aroyl, alkyl, alkoxy, halogen, carboalkyl, alkylcarbamate,alkylcarbonate, alkylsulfonate, alkylsulfamate, semipermeable polymerforming groups, and the like, wherein the organic moieties contain 1 to12 carbon atoms, preferably 1 to 8 carbon atoms.

As the typical semipermeable compositions, one member, or two or moremembers selected from the group consisting of cellulose acylate,cellulose diacylate, cellulose triacylate, cellulose acetate, cellulosediacetate, cellulose triacetate, mono-, di-, and tri-cellulosealkanylates, mono-, di-, and tri-alkenylates, mono-, di-, andtri-aroylates, and the like, may be used. Representative polymersinclude cellulose acetate having a DS of 1.8 to 2.3 and an acetylcontent of 32 to 39.9%; cellulose diacetate having a DS of 1 to 2 and anacetyl content of 21 to 35%; cellulose triacetate having a DS of 2 to 3and an acetyl content of 34 to 44.8%; and the like.

More specific cellulosic polymers include cellulose propionate having aDS of 1.8 and a propionyl content of 38.5%; cellulose acetate propionatehaving an acetyl content of 1.5 to 7% and an acetyl content of 39 to42%; cellulose acetate propionate having an acetyl content of 2.5 to 3%,an average propionyl content of 39.2 to 45%, and a hydroxyl content of2.8 to 5.4%; cellulose acetate butyrate having a DS of 1.8, an acetylcontent of 13 to 15%, and a butyryl content of 34 to 39%; celluloseacetate butyrate having an acetyl content of 2 to 29%, a butyryl contentof 17 to 53%, and a hydroxyl content of 0.5 to 47%; cellulosetriacylates having a DS of 2.6 to 3, such as cellulose trivalerate,cellulose trilamate, cellulose tripalmitate, cellulose trioctanoate, andcellulose tripropionate; cellulose diesters having a DS of 2.2 to 2.6,such as cellulose disuccinate, cellulosedipalmitate, cellulosedioctanoate, cellulose dicaprylate, and the like; mixed celluloseesters, such as cellulose acetate valerate, cellulose acetate succinate,cellulose propionate succinate, cellulose acetate octanoate, cellulosevalerate palmitate, cellulose acetate heptanoate, and the like.Semipermeable polymers are disclosed in U.S. Pat. No. 4,077,407, and canbe synthesized and obtained by procedures described in Encyclopedia ofPolymer Science and Technology, Vol. 3, pp. 325-354 (1964), IntersciencePublishers Inc., New York, N.Y. The content of the polymers is notparticularly limited, so long as it is an amount permeable to thepassage of an external fluid, such as water and biological fluids, andsubstantially impermeable to the passage of compound A, an osmoagent, anosmopolymer, and the like. The content of the polymers is preferably 6to 20 W/W %, more preferably 8 to 18 W/W %, with respect to the weightof a dilayered compressed core consisting of a drug layer and a pushlayer.

Semipermeable polymers for forming the semipermeable membrane furtherinclude cellulose acetaldehyde dimethyl acetate; cellulose acetateethylcarbamate; cellulose acetate methyl carbamate; cellulosedimethylaminoacetate; semipermeable polyurethanes; semipermeablesulfonate polystyrenes; cross-linked selectively semipermeable polymersformed by the coprecipitation of an anion and a cation, as disclosed inU.S. Pat. Nos. 3,173,876, 3,276,586, 3,541,005, 3,541,006, and3,546,142; semipermeable polymers, as disclosed in U.S. Pat. No.3,133,132; semipermeable polystyrene derivatives; semipermeable poly(sodium styrenesulfonate); semipermeable poly(vinylbenzyltrimethylammonium chloride); and semipermeable polymersexhibiting a fluid permeability of 10⁻⁵ to 10⁻² (cc mL/cm hr atm),expressed as hydrostatic or osmotic pressure differences per atmosphereacross a semipermeable membrane. These polymers are described in U.S.Pat. Nos. 3,845,770, 3,916,899, and 4,160,020, and in Handbook of CommonPolymers, Scott and Roff (1971) CRC Press, Cleveland, Ohio.

The semipermeable membrane may contain a flux-regulating agent. Theflux-regulating agent means a substance added to assist in regulatingthe fluid permeability or flux through the semipermeable membrane. Theflux-regulating agents include a substance which enhances the flux(hereinafter referred to as flux-enhancing agent) and a substance whichdecreases the flux (hereinafter referred to as flux-decreasing agent).The flux-enhancing agents are essentially hydrophilic, while theflux-decreasing agents are essentially hydrophobic. The flux-regulatingagents include, for example, polyhydric alcohols, polyalkylene glycols,polyalkylenediols, polyesters of alkylen glycols, and the like.

Typical flux-enhancing agents include polyethylene glycols 300, 400,600, 1500, 4000, 6000 and the like; low molecular weight glycols, suchas polypropylene glycol, polybutylene glycol, and polyamylene glycol:polyalkylenediols, such as poly(1,3-propanediol), poly(1,4-butanediol),poly(1,6-hexanediol), and the like; fatty acids, such as 1,3-butylenglycol, 1,4-pentamethylene glycol, 1,4-hexamethylene glycol, and thelike; alkylen triols, such as glycerine, 1,2,3-butanetriol,1,2,4-hexanetriol, 1,3,6-hexanetriol, and the like; esters, such asethylene glycol dipropionate, ethylene glycol butyrate, butylene glycoldipropionate, glycerol acetate esters, and the like. Preferredflux-enhancing agents include difunctional block-copolymers of propyleneglycol, polyoxyalkylene or derivatives thereof, known as pluronics(trademark, BASF).

Typical flux-decreasing agents include phthalates substituted with analkyl or alkoxy or with both an alkyl and alkoxy group such as diethylphthalate, dimethoxyethyl phthalate, dimethyl phthalate, and[di(2-ethylhexyl) phthalate], and aryl phthalates such as triphenylphthalate and butyl benzyl phthalate; insoluble salts such as calciumsulfate, barium sulfate, calcium phosphate, and the like; insolubleoxides such as titanium oxide; polymers in the form of powder, granules,and the like, such as polystyrene, polymethylmethacrylate,polycarbonate, and polysulfone; esters such as citric acid estersesterified with long chain alkyl groups; inert and water impermeablefillers; resins compatible with cellulose based semipermeable membraneforming materials; and the like.

The content of the flux-regulating agent contained in the semipermeablemembrane is approximately 0.01 to approximately 20 W/W % or more.

Other substances may be contained in the semipermeable membrane toimpart plasticity, flexibility, and elongation properties, to make themembrane less brittle, and to render tear strength. Such substancesinclude phthalate plasticizers such as dibenzyl phthalate, dihexylphthalate, butyl octyl phthalate, straight chain phthalates having 6 to11 carbon atoms, di-isononyl phthalte, di-isodecyl phthalate, and thelike. Other plasticizers include nonphthalates such as triacetin,dioctylazelate, epoxidized tallate, tri-isoctyl trimellitate,tri-isononyl trimellitate, sucrose acetate isobutyrate, epoxidizedsoybean oil, and the like.

The content of the plasticizer contained in the semipermeable membraneis approximately 0.01 to 20 W/W % or more.

The push layer is in contacting layered arrangement with the drug layer.The push layer contains an osmopolymer that imbibes an aqueous orbiological fluid and swells to push compound A through the exit means ofthe formulation. The osmopolymer as used herein means a polymer thatinteracts with water or aqueous biological fluids and swells or expandsto a high degree. Preferred osmopolymers are swellable and hydrophilicpolymers exhibiting a 2 to 50-fold volume increase. The osmopolymer canbe non-crosslinked or crosslinked, but is preferably at least lightlycrosslinked in a preferred embodiment, to create an extended polymernetwork that is too large to exit the formulation. The content of theosmopolymer can be appropriately selected in accordance with variousfactors such as properties, content, and the like of a drug contained inthe drug layer, but is not particularly limited, so long as it is anamount capable of releasing the drug from the drug layer at a desireddissolution rate by swelling. The amount is preferably 30 mg or more,more preferably 50 mg or more. The content is 40 to 80 W/W % withrespect to the weight of the push layer.

The osmopolymers include one or more members selected from the groupconsisting of poly(alkylen oxide) having a number average molecularweight of 1,000,000 to 15,000,000, as represented by polyethylene oxide,and poly(alkali carboxymethylcellulose) having a number averagemolecular weight of 500,000 to 3,500,000, wherein the alkali is sodium,potassium, or lithium. The osmopolymers further include osmopolymerscomprising polymers that form hydrogels, such as Carbopole (registeredtrademark), acidic carboxypolymers, polymers of acrylic cross-linkedwith polyallyl sucrose (known as carboxypolymethylene), and carboxyvinylpolymers having a molecular weight of 250,000 to 4,000,000; Cyanamer(registered trademark) polyacrylamides; cross-linked water swellableindenemaleic anhydride polymers; Good-rite (registered trademark)polyacrylic acid having a molecular weight of 80,000 to 200,000;Aqua-Keeps (registered trademark), acrylate polymer polysaccharidescomposed of condensed glucose units, such as diester cross-linkedpolygluran; and the like. Polymers that form hydrogels are described inU.S. Pat. Nos. 3,865,108, 4,002,173, and 4,207,893, and in Handbook ofCommon Polymers, Scott and Roff, Chemical Rubber Co., Cleveland, Ohio.

The osmoagent (sometimes referred to as an osmotic solute or anosmotically effective agent) may be contained in both of the drug layercontaining compound A and the push layer, and is not particularlylimited, so long as it exhibits an osmotic activity gradient across thesemipermeable membrane. Suitable osmagents include a member or two ormore members selected from the group consisting of sodium chloride,potassium chloride, lithium chloride, magnesium sulfate, magnesiumchloride, potassium sulfate, sodium sulfate, lithium sulfate, potassiumacid phosphate, mannitol, glucose, lactose, sorbitol, inorganic salts,organic salts, and carbohydrates. The content of the osmoagent used is15 to 40 W/W % with respect to the weight of the push layer.

Solvents suitable for manufacturing the formulation components includeaqueous or inert organic solvents that do not adversely harm thesubstances used in the system. Such solvents broadly include one or moremembers selected from the group consisting of aqueous solvents,alcohols, ketones, esters, ethers, aliphatic hydrocarbons, halogenatedsolvents, cycloaliphatic solvents, aromatic solvents, heterocyclicsolvents, and mixtures thereof. Typical solvents include acetone,diacetone alcohol, methanol, ethanol, isopropyl alcohol, butyl alcohol,methyl acetate, ethyl acetate, isopropyl acetate, n-butyl acetate,methyl isobutyl ketone, methyl propyl ketone, n-hexane, n-heptane,ethylene glycol monoethyl ether, ethylene glycol monoethyl acetate,methylene dichloride, ethylene dichloride, propylene dichloride, carbontetrachloride, nitroethane, nitropropane, tetrachloroethane, ethylether, isopropyl ether, cyclohexane, cyclooctane, benzene, toluene,naphtha, 1,4-dioxane, tetrahydrofuran, diglyme, water, aqueous solventscontaining inorganic salts (such as sodium chloride, calcium chloride,and the like), and mixtures thereof (such as acetone and water, acetoneand methanol, acetone and ethyl alcohol, methylene dichloride andmethanol, and ethylene dichloride and methanol).

The drug layer is formed from a pharmaceutical composition consisting ofcompound A in an amount pharmacologically effective in treatment orprevention, and a carrier for a sustained release pharmaceuticalcomposition. The carrier for a sustained release pharmaceuticalcomposition may include hydrophilic polymers.

The hydrophilic polymers impart an action of releasing compound A at aconstant releasing rate. Suitable hydrophilic polymers includepoly(alkylene oxide) having a number average molecular weight of 100,000to 750,000, such as poly(ethylene oxide), poly(methylene oxide),poly(buthylene oxide, and poly(hexylene oxide); and poly(carboxymethylcellulose) having a number average molecular weight of 40,000 to400,000, typically poly(alkali carboxymethyl cellulose), poly(sodiumcarboxymethyl cellulose), poly(potassium carboxymethyl cellulose), andpoly(lithium carboxymethyl cellulose). The drug composition may containhydroxypropylalkyl cellulose having a number average molecular weight of9,200 to 125,000, typically hydroxypropylethyl cellulose, hypromellose,hydroxypropylbutyl cellulose, and hydroxypropylpentyl cellulose, toimprove delivery properties of the formulation; and polyvinylpyrrolidonehaving a number average molecular weight of 7,000 to 75,000, to improveflow properties of the formulation. Among these polymers, poly(ethyleneoxide) having a number average molecular weight of 100,000 to 300,000 ismost preferable. The content of the hydrophilic polymer can beappropriately selected in accordance with various factors such asphysicochemical properties, content, and the like of a drug contained,but is 40 to 90 W/W % with respect to the drug layer.

The drug layer may further contain surfactants and disintegrants, ifdesired. Suitable surfactants are those having an HLB value ofapproximately 10 to 25, such as polyethylene glycol 400 monostearate,polyoxyethylene-4-sorbitan monolaurate, polyoxyethylene-20-sorbitanmonooleate, polyoxyethylene-20-sorbitan monopalmitate,polyoxyethylene-20-monolaurate, polyoxyethylene-40-stearate, sodiumoleate, and the like. Disintegrants may be selected from starches,clays, celluloses, algins and gums and crosslinked starches, cellulosesand polymers. Representative disintegrants include corn starch, potatostarch, croscarmelose, crospovidone, sodium starch glycolate, Veegum HV,methylcellulose, agar, bentonite, carboxymethylcellulose, alginic acid,guar gum, and the like.

Pan coating may be used to prepare the completed formulation, except forthe exit orifice for releasing a drug from the surface of theformulation. In the pan coating system, the composition for forming thesemipermeable membrane is deposited by spraying the composition onto thesurface of the bilayered compressed core formed from the drug layer andthe push layer, accompanied by tumbling in a rotating pan.Alternatively, the compressed core may be coated with the semipermeablemembrane by well-known techniques in the art. After the coating, thesemipermeable membrane may be dried in a forced-air oven or in atemperature and humidity controlled oven to remove the solvent(s) usedin the coating from the formulation. Drying conditions may beappropriately selected on the basis of an available equipment, ambientconditions, solvents, a coating agent, a coating thickness, and thelike.

The osmotic pump type formulation, an embodiment of the pharmaceuticalcomposition for modified release of the present invention, can beprepared by known conventional methods, such as wet granulationtechniques. In the wet granulation, a drug and a carrier for a sustainedrelease pharmaceutical composition are blended using an organic solvent,such as denatured absolute alcohol and the like, as a granulationsolution. The remaining components may be dissolved in a portion of thegranulation solution such as the above solvent, and a wet mixtureseparately prepared is gradually added to the drug mixture, accompaniedby the continuous mixing in a blender. The granulation solution is addeduntil a wet aggregate is generated, and the wet aggregate are siftedthrough a screen arranged on an oven tray. The mixture is dried at atemperature of approximately 24 to 35° C. in a forced-air oven forapproximately 18 to 24 hours. The dried granules are sized. A lubricantsuch as magnesium stearate or the like is added to the drug granules,and the whole is put into a milling jar and mixed on a jar mill forapproximately 10 minutes. The composition is pressed into a layer, forexample, in a Manestye (registered trademark) press or a Korsch LCTpress. For a bilayered core, the drug-containing layer is pressed, and acomposition for the push layer, prepared in a similar fashion by wetgranulation techniques, is pressed against the drug-containing layer.One exit orifice, or two more exit orifices, are drilled in the druglayer end of the formulation. Optional water soluble overcoats, whichmay be colored (for example, Opadry colored coatings) or clear (forexample, Opadry Clear), may be coated on the formulation to provide thecompleted formulation.

The osmotic pump type formulation, an embodiment of the pharmaceuticalcomposition for modified release of the present invention, has at leastone exit orifice. A drug is constantly released from the formulationthrough the exit orifice(s) by the compressed core. The exit orifice maybe provided during the manufacture of the formulation, or during thedrug delivery by the formulation in a fluid environment of use. Theterms “exit orifice”, “delivery exit”, “drug delivery exit”, and similarterms as used herein include terms selected from the group consisting ofpass, opening, orifice, and bore. Further, these expressions include anorifice that is formed from a substance or polymer that erodes,dissolves or is leached from the outer wall.

This substance or polymer may include, for example, erodiblepoly(glycolic acid) or poly(lactic acid) in the semipermeable membrane;gelatinous filaments; water-removable polyvinyl alcohol); a leachablecompound, such as a fluid removable pore-forming substance selected fromthe group consisting of inorganic and organic salts, oxides, andcarbohydrates. The exit(s) are formed by leaching one or two or moremembers selected from the group consisting of sorbitol, lactose,fructose, glucose, mannose, galactose, talose, sodium chloride,potassium chloride, sodium citrate and mannitol to provide auniform-release dimensioned pore-exit orifice(s). The exit can have anyshape, such as round, rectangle, square, elliptical, and the like, forthe uniform release of a drug from the formulation. The formulation canbe constructed with one or two or more exits in spaced-apart relation oron one or more surfaces of the formulation. The pore size of the exit isnot particularly limited, so long as it can cooperate with thecompressed core to control the release of the drug, but is preferably0.3 to 0.6 mm. Drilling, including mechanical and laser drilling,through the semipermeable membrane can be used to form the exit orifice.Such exits and equipments for forming such exits are disclosed in U.S.Pat. No. 3,916,899, by Theeuwes and Higuchi and in U.S. Pat. No.4,088,864, by Theeuwes, et al., each of which is incorporated herein byreference.

(5) Formulation Utilizing Swelling Polymer

The formulation utilizing a swelling polymer, as an embodiment of thepharmaceutical composition for modified release of the presentinvention, is a formulation for modified release containing awater-soluble high molecular weight polymer which swells upon imbibitionof water.

Formulation techniques using a swelling polymer which may be used in theformulation for modified release of the present invention are describedin U.S. Pat. Nos. 6,340,475, 5,972,389, 5,582,837, and 5,007,790, thecontents of which are incorporated herein by reference.

The “water-soluble high molecular weight polymer which swells uponimbibition of water” used is not particularly limited, so long as it isa pharmaceutically acceptable polymer that swells in a dimensionallyunrestricted manner upon imbibition of water, and that releases a drugcontinuously. Suitable polymers are those having a weight averagemolecular weight of preferably approximately 4,500,000 or more, morepreferably approximately 4,500,000 to approximately 10,000,000, mostpreferably approximately 5,000,000 to approximately 8,000,000.

Such polymers include cellulose polymers and derivatives thereof,polysaccharides and derivatives thereof, polyalkylene oxides, andcrosslinked polyacrylic acids and derivatives thereof. The term“cellulose” as used herein means a linear polymer of anhydroglucose.Preferred cellulose polymers are alkyl-substituted cellulose polymersthat dissolve in the gastrointestinal tract. Preferred alkyl-substitutedcellulose derivatives are those substituted with alkyl groups having 1to 3 carbon atoms each. Examples thereof include, for example,methylcellulose, hydroxymethylcellulose, hydroxyethylcellulose,hydroxypropylcellulose, hypromellose, and carboxymethylcellulose. Apreferred viscosity ranges between approximately 100 and approximately110,000 cps, as measured in a 2% aqueous solution at 20° C. A viscosityin other embodiments ranges between approximately 1,000 andapproximately 4,000 cps, as measured in a 2% aqueous solution at 20° C.More preferred alkyl-substituted celluloses are hydroxyethylcelluloseand hypromellose. Preferred hydroxyethylcellulose is NATRASOL (productname) 250H×NF.

Further, most preferred polymers are polyalkylene oxide derivatives,particularly polyethylene oxide, i.e., an unsubstituted linear polymerof ethylene oxide. Preferred polyethylene oxide has a weight averagemolecular weight of approximately 900,000 to approximately 8,000,000. Apreferred viscosity ranges between approximately 50 to approximately2,000,000 cps, as measured in a 2% aqueous solution at 20° C. Preferredpolyethylene oxide is POLYOX (product name), such as grade WSR Coagulantand grade WSR 303

Other examples of such polymers include both naturally-occurring andmodified (semi-synthetic) polysaccharide gums, such as dextran, xanthangum, gellan gum, welan gum, and rhamsan gum. Xanthan gum is preferred.Crosslinked polyacrylic acids of greatest utility are those whoseproperties are the same as those described above for alkyl-substitutedcelluloses and polyalkylene oxide polymers. Preferred crosslinkedpolyacrylic acids are those with a viscosity ranging from approximately4,000 to approximately 40,000 cps, for a 1% aqueous solution at 25° C.Preferred examples are CARBOPOL (product name) NF grades 971P, 974P, and934P, and WATER LOCK (product name) which arestarch/acrylates/acrylamide copolymers.

The content of the “water-soluble high molecular weight polymer whichswells upon imbibition of water” with respect to the weight of theformulation is not particularly limited, but is preferably approximately1 to approximately 95 W/W %.

The formulation utilizing a swelling polymer, an embodiment of thepharmaceutical composition for modified release of the presentinvention, can be prepared as a pharmaceutically acceptable solid dosageform for oral administration such as tablets, particles, and particlesretained in tablets or capsules. A presently preferred dosage form is asize 0 gelatin capsule containing two or three polymer particles(pellets) containing a drug. For the two-pellet capsules, the pelletsare cylindrically shaped, 6.6 or 6.7 mm (or more generally, 6.5 to 7 mm)in diameter and 9.5 or 10.25 mm (or more generally, 9 to 12 mm) inlength. For the three-pellet capsules, the pellets are cylindricallyshaped, 6.6 mm in diameter and 7 mm in length. For a size 00 gelatincapsule with two pellets, the pellets are cylindrical, 7.5 mm indiameter and 11.25 mm in length. For a size 00 gelatin capsule withthree pellets, the pellets are cylindrical, 7.5 mm in diameter and 7.5mm in length. Another presently preferred dosage form is a tablet, withdimensions 18 to 22 mm in length, 6.5 to 7.8 mm in width, and 6.2 to 7.5mm in height, more preferably with dimensions 20 mm in length, 6.7 mm inwidth, and 6.4 mm in height. These are merely examples, and the shapesand sizes can be varied considerably.

A particulate drug/polymer mixture or a drug-impregnated polymer matrixcan be prepared by various known conventional methods, such as mixing,comminution, and fabrication techniques. These methods include, forexample, direct compression using appropriate punches and dies,injection, and compression molding. When compression molding is carriedout, lubricants may be optionally added. Examples of lubricants includestearic acid, magnesium stearate, calcium stearate, sodium stearylfumarate, and the like, and magnesium stearate is preferred. The contentof the lubricant is 0.25 to 3 W/W %, preferably less than 1 W/W %, withrespect to the weight of the formulation. As other lubricants,hydrogenated vegetable oils, and hydrogenated and refined triglyceridesof stearic and palmitic acids are preferable, and the content isapproximately 1 to 5 W/W %, preferably approximately 2 W/W %, withrespect to the weight of the formulation.

Most preferable sets of various components described above include acombination of approximately 90 to approximately 97 W/W % (with respectto the weight of the formulation) of polyethylene oxide having a weightaverage molecular weight of approximately 2,000,000 to approximately7,000,000 as the “water-soluble high molecular weight polymer whichswells upon imbibition of water” and less than approximately 2 W/W %(with respect to the weight of the formulation) of magnesium stearate asthe lubricant. Examples of a combination of, for example, twowater-soluble polymers include a combination of approximately 48 W/W %of polyethylene oxide having a weight average molecular weight ofapproximately 900,000 to approximately 7,000,000 and approximately 48W/W % of hypromellose having a viscosity of approximately 3 toapproximately 10,000 cps, as measured in a 2% aqueous solution at 20° C.(weight ratio=about 1:1).

It is expected that the formulation utilizing a swelling polymer isretained in the stomach by swelling.

(6) Matrix Formulation Utilizing Water-Soluble Polymer

The matrix formulation utilizing water-soluble polymer, an embodiment ofthe pharmaceutical composition for modified release of the presentinvention, is a formulation for modified release in which the drug ishomogenously dispersed in one or more water-soluble polymers, such ashypromellose (HPMC).

Techniques for obtaining such a matrix formulation which may be used inthe formulation for modified release according to the present inventionare disclosed, for example, in WO 93/16686, the contents of which areincorporated herein by reference.

When hypromellose, a water-soluble polymer, is brought into contact withwater, hydration thereof is caused, and a hydrogel layer is formed onthe surface of a matrix. This gel layer containing a drug formed on thematrix surface is gradually dissolved and eroded, to release the drugfrom the layer. The matrix formulation of the present invention ischaracterized in that a drug may be controllably released by repeatingthe contact with water, the formation of the gel layer containing thedrug, and the dissolution and erosion of the gel layer.

The matrix formulation of the present invention is characterized in thata sustained release filler consisting of a water-soluble polymer, aninactive diluent, and a physiologically active substance arehomogenously dispersed. The water-soluble polymer is not particularlylimited, so long as it is gradually gelled, eroded, dissolved, and/ordisintegrated when exposed to an environmental fluid. Examples of thewater-soluble polymers include, for example, hypromellose having amolecular weight of 1,000 to 4,000,000, hydroxymethyl cellulose,hydroxyethyl cellulose, hydroxypropyl cellulose having a molecularweight of 2,000 to 2,000,000, hypromellose phthalate having a labeledviscosity of 30 to 200 mm²/s [at 20° C.; a 10% solution prepared bydissolving hypromellose phthalate in a methanol/dichloromethane mixture(1:1)], carboxyvinyl polymers, chitosans, mannans, galactomannans,xanthans, carageenans, amylose, alginic acid, salts and derivativesthereof, pectin, acrylates, aminoalkylmethacrylate copolymers,methacrylate copolymers, polyacid anhydrides, polyamino acids,poly(methylvinyl ether/maleic anhydride) polymers, polyvinyl alcohols,polyvinylpyrrolidone, glucans, scleroglucans, carboxymethyl celluloseand derivatives thereof, methyl cellulose, or conventional water-solublecellulose derivatives. Hypromellose having a molecular weight of 1,000to 2,000,000, or carboxyvinyl polymers of 3,000 to 45,000 cps (at 25°C.; a 0.5% aqueous solution) is preferable, and hypromellose having amolecular weight of 10,000 to 1,000,000, or carboxyvinyl polymers of4,000 to 40,000 cps (at 25° C.; a 0.5% aqueous solution) is morepreferable. The content of the water-soluble polymer is 10 W/W % or moreper formulation unit, preferably 30 W/W % or more, more preferably 70W/W % or more. These water-soluble polymers may be contained alone or asa combination thereof in an appropriate amount(s).

Various fillers for medicaments may be appropriately used to prepare thematrix formulation of the present invention. The fillers for medicamentsare not particularly limited, so long as they are pharmaceuticallyacceptable and may be used as additives for medicament. As the fillers,for example, a diluent, a binder, a disintegrator, an acidulant, aneffervescent agent, an artificial sweetener, a flavor, a lubricant, acoloring agent, or the like may be used. The diluent may be selectedfrom mannitol, lactose, starches derived from various organs, sorbitol,xylitol, citric acid, microcrystalline cellulose, and/or a diluentcapable of generally promoting a penetration of water or an aqueousliquid into a pharmaceutical preparation. The binders include, forexample, hypromellose, hydroxypropyl cellulose, polyvinyl alcohol,methyl cellulose, gum arabic, and the like. The disintegrators include,for example, a corn starch, a starch, carmellose calcium, carmellosesodium, low-substituted hydroxypropyl cellulose, and the like. Theacidulants include, for example, citric acid, tartaric acid, malic acid,and the like. The effervescent agents include, for example, sodiumbicarbonate and the like. The artificial sweeteners include, forexample, saccharin sodium, dipotassium glycyrrhizinate, aspartame,stevia, thaumatin, and the like. The flavors include, for example,lemon, lemon-lime, orange, menthol, and the like. The lubricantsinclude, for example, magnesium stearate, calcium stearate, sucrosefatty acid esters, polyethylene glycol, talc, stearic acid, and thelike. These fillers for medicaments may be contained alone or as acombination thereof in an appropriate amount(s).

The matrix formulation of the present invention may be manufactured by aknown method per se. In particular, tablets may be manufactured by atablet forming method which is commonly used and known to those skilledin the art. The tabletting pressure is generally within a range of 3 to20 kN. In a small scale, tablets may be prepared, in accordance withmethods explained in detail in the following Examples, by preparingpowder and/or granules with a mortar and a pestle, and forming thepowder and/or granules into tablets by using an oil press tablettingmachine.

(7) Modified Release Formulation with Coating Membrane

As a method for controlling the release (i.e., modified release) of adrug from a pharmaceutical preparation, a coating membrane is applied tothe surface of a pharmaceutical preparation by coating. The kind ofcoating membrane is not particularly limited. The coating may be appliedto not only a shaped preparation such as a tablet or the like, but alsovarious preparations such as powder, granules, pellets, or the like.

A coating liquid may contain, for example, a membrane forming agent(mainly a polymer), a plasticizer (which provides plasticity,flexibility, and extensibility to a coating membrane), a water-solublebase (such as lactose, sodium chloride, or the like), a dispersing agent(which prevents particles or tablets from adhering and aggregating afterthe coating), or the like. These components may be dissolved ordispersed in an appropriate solvent, such as water, alcohol, or thelike, to prepare the coating liquid.

The release of a drug from the formulation can be controlled byappropriately adjusting, for example, the kinds and the mixing ratio ofcomponents contained in the coating liquid, the amount of coating, orthe like. For example, a preferable ratio of the membrane forming agentto the water-soluble base is 99:1 to 50:50 (membrane forming agent:water-soluble base). The content of the coating membrane is preferablyapproximately 2 to 30 parts by weight, with respect to 100 parts byweight of an uncoated tablet.

Examples of a coating method include, for example, a method in which acoating liquid, such as an organic solvent solution, or a mixingsolution or suspension of an organic solvent and water, is sprayed whilebeing rotated, by using a coating pan, or a method in which a coatingliquid is sprayed while being fluidized by air blown from the bottom ofa fluidized bed. Further, a coating liquid prepared by dissolving ordispersing a membrane forming agent in a solvent may be sprayed, andthen the solvent may be removed by drying to form a coating membrane onthe surface of a pharmaceutical preparation. As a simple method, acoating membrane may be formed by immersing shaped preparations or thelike in a coating liquid.

Examples of the membrane forming agent as used herein include, forexample, a water-insoluble polymer or a water-soluble polymer. Themembrane forming agent is not particularly limited, so long as it ispharmaceutically acceptable and biocompatible. These membrane formingagents may be added alone or as a combination thereof in an appropriateamount(s).

Examples of the water-insoluble polymer include, for example, dibenzylphthalate, dihexyl phthalate, butyl octyl phthalate, beeswax, carnaubawax, cetyl alcohol, cetyl stearyl alcohol, glyceryl behenate, lipids,fats, resins such as shellac or the like, cellulose derivatives such asethyl cellulose, cellulose acetate, or the like, polyacrylatederivatives such as aminoalkylmethacryl copolymer (product name:Eudragit RS) or the like, polymethacrylate derivatives such asmethacrylate copolymer (product name: Eudragit L) or the like,hydroxypropylmethyl cellulose acetate succinate, polylactic acid,polyglycolic acid, or the like.

Examples of the water-soluble polymer include, for example,hypromellose, hydroxypropyl cellulose, hydroxyethyl cellulose,carmellose sodium, methyl cellulose, polyvinylpyrrolidone, polyethyleneglycol, polyvinyl alcohol, or the like.

To enhance the hydrophilic property of the coating membrane, awater-soluble base may be added. Examples of the water-soluble baseinclude, for example, maltose, sucrose, lactose, sodium chloride, citricacid, polyethylene glycol 400, dextrose, fructose, xylitol,polyoxyethylene sorbitan monooleate, or the like.

The coating liquid which may be used in the present invention preferablycontains one or more of the above-mentioned water-insoluble polymers,and more preferably further contains one or more of the water-solublepolymers and/or one or more of the water-soluble bases.

Further, the coating liquid may contain a plasticizer to provideplasticity, flexibility, and extensibility to the coating membrane.Examples of the plasticizer include, for example, triacetin, dioctylazelate, epoxidized tallate, triisooctyl trimellitate, triisononyltrimellitate, sucrose acetate isobutyrate, soybean oil, propyleneglycol, glycerol, polyethylene glycol, glyceryl triacetate (triacetin),triethyl citrate, acetyl triethyl citrate, diethyl phthalate, diethylsebacate, dibutyl sebacate, acetylated monoglyceride, castor oil, liquidparaffin, or the like.

If desired, a surfactant and/or a disintegrator may be added. As such asurfactant which may be used in the coating membrane, a surfactanthaving an HLB value of approximately 10 to 25, such as polyethyleneglycol 400 monostearate, polyoxyethylene-4-sorbitan monolaurate,polyoxyethylene-20-sorbitan monooleate, polyoxyethylene-20-sorbitanmonopalmitate, polyoxyethylene-20-monolaurate,polyoxyethylene-40-stearate, sodium oleate, or the like, may be used.

Examples of the disintegrator include, for example, starches, clay,cellulose, algin, gums, crosslinked starches, crosslinked cellulose, orcrosslinked polymers. Typically, for example, corn starch, potatostarch, croscarmellose, crospovidone, sodium starch glycorate, VeegumHV, methyl cellulose, agar, bentonite, carboxyl methyl cellulose,alginic acid, guar gum, or the like, may be used.

As a solvent suitable for manufacturing the formulation of the presentinvention, an aqueous or inert organic solvent which does not adverselyaffect substances used in the system may be used. Examples of thesolvent include, for example, aqueous solvents, alcohols, ketones,esters, ethers, aliphatic hydrocarbons, halogenated solvents,cycloaliphatic, aromatic, or heterocyclic solvents, or a mixturethereof. Typical solvents may be, for example, acetone, diacetonealcohol, methanol, ethanol, isopropanol, butanol, methyl acetate, ethylacetate, isopropyl acetate, n-butyl acetate, methyl isobutyl ketone,methyl propyl ketone, n-hexane, n-heptane, ethylene glycol monoethylether, ethylene glycol monoethyl acetate, methylene dichloride, ethylenedichloride, propylene dichloride, carbon tetrachloride, nitroethane,nitropropane, tetrachloroethane, ethyl ether, isopropyl ether,cyclohexane, cyclooctane, benzene, toluene, naphtha, 1,4-dioxane,tetrahydrofuran, diglyme, water, an aqueous solvent containing aninorganic salt such as sodium chloride, calcium chloride, or the like,or a mixture thereof, such as a mixture of acetone and water, a mixtureof acetone and methanol, a mixture of acetone and ethanol, a mixture ofmethylene dichloride and methanol, or a mixture of ethylene dichlorideand methanol.

(8) Matrix Formulation Utilizing Insoluble Polymer

A matrix formulation utilizing an insoluble polymer, an embodiment ofthe present invention, is a pharmaceutical composition for modifiedrelease in which the drug is uniformly dispersed in a water-insolublepolymer. Because the matrix consisting of the water-insoluble polymercan control the penetration of water into the formulation, the matrixformulation can modify the release of the drug from the formulation bycontrolling the dissolution rate of the drug in the matrix and thedispersion rate of the dissolved drug in the matrix.

The water-insoluble polymer used in the present invention is notparticularly limited, so long as it is pharmaceutically acceptable.Examples of the water-insoluble polymer include, for example, dibenzylphthalate, dihexyl phthalate, butyl octyl phthalate, beeswax, carnaubawax, cetyl alcohol, cetyl stearyl alcohol, glyceryl behenate, lipids,fats, resins such as shellac or the like, cellulose derivatives such asethyl cellulose, cellulose acetate, or the like, polyacrylatederivatives such as aminoalkylmethacryl copolymer or the like,polymethacrylate derivatives such as methacrylate copolymer, ethylacrylate methyl methacrylate copolymer or the like, hydroxypropylmethylcellulose acetate succinate, polylactic acid, polyglycolic acid, or thelike.

The content of the insoluble polymer is 1 W/W % or more per formulationunit, preferably 2 W/W % or more, more preferably 5 W/W % or more. Theseinsoluble polymers may be contained alone or as a combination thereof inan appropriate amount(s).

Various fillers for medicaments may be appropriately used to prepare thematrix formulation of the present invention. The fillers for medicamentsare not particularly limited, so long as they are pharmaceuticallyacceptable and may be used as additives for medicament. As the fillers,for example, a diluent, a binder, a disintegrator, an acidulant, aneffervescent agent, an artificial sweetener, a flavor, a lubricant, acoloring agent, or the like may be used. The diluent may be selectedfrom mannitol, lactose, starches derived from various organs, sorbitol,xylitol, citric acid, microcrystalline cellulose, and/or a diluentcapable of generally promoting a penetration of water or an aqueousliquid into a pharmaceutical preparation. The binders include, forexample, hypromellose, hydroxypropyl cellulose, polyvinyl alcohol,methyl cellulose, gum arabic, and the like. The disintegrators include,for example, a corn starch, a starch, carmellose calcium, carmellosesodium, low-substituted hydroxypropyl cellulose, and the like. Theacidulants include, for example, citric acid, tartaric acid, malic acid,and the like. The effervescent agents include, for example, sodiumbicarbonate and the like. The artificial sweeteners include, forexample, saccharin sodium, dipotassium glycyrrhizinate, aspartame,stevia, thaumatin, and the like. The flavors include, for example,lemon, lemon-lime, orange, menthol, and the like. The lubricantsinclude, for example, magnesium stearate, calcium stearate, sucrosefatty acid esters, polyethylene glycol, talc, stearic acid, and thelike. These fillers for medicaments may be contained alone or as acombination thereof in an appropriate amount(s).

The matrix formulation of the present invention may be manufactured by aknown method per se. In particular, tablets may be manufactured by atablet forming method which is commonly used and known to those skilledin the art. The tabletting pressure is generally within a range of 3 to20 kN. In a small scale, tablets may be prepared, in accordance withmethods explained in detail in the following Examples, by preparingpowder and/or granules with a mortar and a pestle, and forming thepowder and/or granules into tablets by using an oil press tablettingmachine.

EXAMPLES

The present invention will now be further illustrated by, but is by nomeans limited to, the following Examples.

In the following Examples, unless otherwise noted, a compound producedaccording to Example 41 of WO 99/20607 was used as compound A.

Example 1 Preparation of Sustained Release Hydrogel-Forming Formulation

In this Example, as the pharmaceutical composition for modified releaseof the present invention, sustained release hydrogel-formingformulations 1A to 1C were prepared.

Example 1A

400 g of the compound A, 100 g of polyethylene oxide, 291.2 g ofpolyethylene glycol, 0.8 g of finely ground dibutyl hydroxytoluene (BHT)(manufactured by Merck, the same was used hereinafter), and 8 g ofmagnesium stearate were weighed out, and mixed by using a mixer. Themixture was compression-molded by using Roller Compactor Mini(manufactured by Freund Corporation; the same apparatus was usedhereinafter) and sieved to obtain a pharmaceutical composition formodified release (granules) of the present invention. The obtainedgranules were formed into tablets by using a rotary tabletting machine(manufactured by HATA IRON WORKS CO., LTD.; the same apparatus was usedhereinafter) to obtain 400 mg/tablet of a pharmaceutical composition formodified release (tablet) of the present invention. The obtained tabletwas coated with a film coating agent dispersed in water (Opadry,manufactured by Colorcon, Inc., the same was used hereinafter) by usingHigh coater (HCT-30, manufactured by Freund Corporation, the sameapparatus was used hereinafter) to obtain a pharmaceutical compositionfor modified release (tablet) of the present invention.

Example 1B

400 g of the compound A, 250 g of polyethylene oxide, 190.7 g ofpolyethylene glycol, 0.8 g of finely ground BHT, and 8.5 g of magnesiumstearate were weighed out, and mixed by using a mixer. The mixture wascompression-molded by using Roller Compactor Mini, and then sieved toobtain a pharmaceutical composition for modified release (granules) ofthe present invention. The obtained granules were formed into tablets byusing a rotary tabletting machine to obtain 425 mg/tablet of apharmaceutical composition for modified release (tablet) of the presentinvention. The obtained tablet was coated with a film coating agentdispersed in water by using High coater to obtain a pharmaceuticalcomposition for modified release (tablet) of the present invention.

Example 1C

Into a fluidized bed granulating apparatus GPCG-5 (manufactured byFreund Corporation; the same apparatus was used hereinafter), 800 g ofde-lumped compound A, 1120 g of polyethylene oxide, 1913.6 g ofpolyethylene glycol, and 120 g of hydroxypropylcellulose (HPC-SL,manufactured by Nippon Soda Co., Ltd.) were loaded, and granulated withpurified water to obtain a pharmaceutical composition for modifiedrelease (granules) of the present invention. The pharmaceuticalcomposition for modified release (granules) of the present invention wassieved, and mixed with 6.4 g of finely ground BHT and 40 g of magnesiumstearate, and the obtained mixture was formed into tablets by using therotary tabletting machine to obtain a pharmaceutical composition formodified release (tablet) of the present invention having a weight pertablet of 250 mg. The obtained tablets were spray-coated with an aqueousdispersion of the film coating agent using HiCoater to obtain apharmaceutical composition for modified release (tablet) of the presentinvention having a weight per tablet of 257.5 mg.

Comparative Example 1

After 400 g of de-lumped compound A was mixed with 1200 g of D-mannitol,320 g of purified water was added thereto, and the mixture was kneadedby using an agitation granulator (VG-25, manufactured by PowrexCorporation). The resulting product was sieved through a screen(opening: 850 μm), and dried by using a fluidized bed granulatingapparatus (FLO-1, manufactured by Freund Corporation). The dried productwas sieved through a screen (opening: 500 μm), and then filled into No.1 capsules at a content of 320 mg per capsule to obtain a pharmaceuticalcomposition of Comparative Example containing 80 mg of compound A.

Example 2 Preparation of Multi-Layered Formulation Consisting of DrugCore and Release-Controlling Layer which are Geometrically Arranged

In the Examples (Examples 2A to 2D), as the pharmaceutical compositionfor modified release of the present invention, multi-layeredformulations 2A to 2D were prepared.

Step 1: Production of Mixed Powder Constituting Layer 2 ContainingActive Substance

A mixed powder containing 50.0 mg of compound A and the composition unitshown in Table 1 was produced, and used in producing layer 2 as theintermediate layer of the three-layered tablet. The powder composed ofthe composition unit was prepared by weighing out necessary amounts ofthe active substance (compound A), mannitol, Hypromellose (90SH-15000,manufactured by Shin-Etsu Chemical Co. Ltd), polyvinyl pyrrolidone,microcrystalline cellulose, and magnesium stearate, and mixing them witha mortar and a pestle so that they were homogenized.

TABLE 1 Compound A 50.0 mg Mannitol 15.0 mg Hypromellose (90SH-15000)15.0 mg Polyvinyl pyrrolidone 4.8 mg Microcrystalline cellulose 63.7 mgMagnesium stearate 1.5 mg Total 150.0 mgStep 2: Production of Granules Constituting Layers 1 and 3 (Layers 1 and3 Containing No Drug) Used for Modified Release of Drug

Granules made with the composition ratio shown in Table 2 were producedand used in producing layer 1 as the top layer and layer 3 as the bottomlayer of the three-layered tablet. Specifically, the granules wereprepared by weighing out necessary amounts of hypromellose, hydrogenatedcastor oil, yellow iron oxide, and magnesium stearate; mixing them bythe use of a mortar and a pestle so that they were homogenized; furthermoistening them with a solution of ethylcellulose in alcohol (10% w/w);and drying the homogeneously wet aggregate.

TABLE 2 Hypromellose (90SH-15000) 80.25% Hydrogenated castor oil 13.50%Yellow iron oxide 0.25% Ethylcellulose 5.00% Magnesium stearate 1.00%Total 100.00%Step 3: Production of Three-Layered Tablet (Compression Molding)

Three-layered tablet were prepared by an oil press tabletting machinewith a tabletting pressure of 1000 kg/punch. The granules of layer 3prepared in Step 2 were put into a die, and subjected to light tappingso that the upper surface became flat. On the surface, the mixed powderof layer 2 containing the active substance prepared in Step 1 wasloaded, which was subjected to light tapping so that the upper surfacebecame flat. Furthermore, on the surface, the granules of the layer 1prepared in the Step 2 were loaded into the die, and subjected tocompression molding. Thus, three-layered tablets containing 50 mg ofcompound A (2A to 2D) were produced.

The weight and the punch diameter of each of layers 1, 2, and 3 in eachof multi-layered formulations 2A to 2D are shown in Table 3.

TABLE 3 Examples 2 A 2 B 2 C 2 D Layer 1 100.0 100.0 100.0 100.0 Layer 2150.0 300.0 150.0 150.0 Layer 3 150.0 150.0 150.0 150.0 Total (mg) 400.0550.0 400.0 400.0 Punch 8 8 7 6.5 diameter (mm)

Example 3 Preparation of Gel Formulation in which a Plurality of Gums isCombined

In this Example, as the pharmaceutical composition for modified releaseof the present invention, a gel formulation composed of the compositionunit shown in Table 4 was prepared.

Specifically, necessary amounts of locust bean gum (GENUGUM typeRL-200-J, manufactured by Sansho Co., Ltd.), xanthan gum (VS-900,manufactured by Nitta Gelatin Inc.), dextrose, and calcium sulfate wereweighed out, and mixed sufficiently by using a mortar and a pestle sothat the mixture was homogenized. Furthermore, an appropriate amount ofpurified water was added thereto, and the mixture was stirred and mixed.The mixture was sieved through a screen, and the obtained product wasdried. To the dried product, a necessary amount of compound A was added.To the mixture, a solution of ethylcellulose in alcohol (100 mg/mL) wasgradually added. The mixture was dried, and the dried product was putinto a die, and subjected to compression molding by an oil presstabletting machine with a tabletting pressure of 1000 kg/punch by usinga punch having a diameter of 8 mm.

TABLE 4 Compound A 50.0 mg Locust bean gum (GENUGUM type RL-200-J) 50.0mg Xanthan gum (VS-900) 50.0 mg Dextrose 70.0 mg Calcium sulfate 10.0 mgEthylcellulose 14.0 mg Total 244.0 mg 

Example 4 Preparation of Osmotic Pump Type Formulation

In this Example, as the pharmaceutical composition for modified releaseof the present invention, an osmotic pump type formulation was prepared.

Step 1: Production of Mixed Powder Constituting Drug Layer ContainingActive Substance

Mixed powder containing 50.0 mg of compound A and the composition unitshown in Table 5 was produced, and it was used in producing a bilayeredcompressed core.

The powder composed of the composition unit was prepared by weighing outnecessary amounts of active substance (compound A), polyethylene oxide(Polyox WSR N-80, manufactured by DOW), hypromellose (TC-5 R,manufactured by Shin-Etsu Chemical Co. Ltd.), and magnesium stearate,and mixing them sufficiently by using a mortar and a pestle so that theywere homogenized.

TABLE 5 Compound A 50.0 mg Polyethylene oxide (Polyox WSR N-80) 100.0 mgHypromellose (TC-5 R) 6.0 mg Magnesium stearate 1.0 mg Total 157.0 mgStep 2: Production of Mixed Powder Constituting Push Layer

A mixed powder composed of the composition unit shown in Table 6 wasproduced, and it was used in producing the bilayered compressed core.

Specifically, the mixed powder was produced by weighing out necessaryamounts of polyethylene oxide (Polyox WSR Coagulant, manufactured byDOW), sodium chloride, hypromellose, red ferric oxide, and magnesiumstearate, and mixing them sufficiently by using a mortar and a pestle sothat they were homogenized.

TABLE 6 Polyethylene oxide (Polyox WSR Coagulant) 60.0 mg Sodiumchloride 30.0 mg Hypromellose (TC-5 R) 4.0 mg Red ferric oxide 1.0 mgMagnesium stearate 0.5 mg Total 95.5 mgStep 3: Production of Bilayered Compressed Core Composed of Drug Layerand Push Layer

A bilayered compressed core was prepared by an oil press tablettingmachine with a tabletting pressure of 1000 kg/punch. The mixed powderfor a push layer prepared in Step 2 was put into a die, the mixed powderfor a drug layer prepared in Step 1 was loaded thereon, and the bothlayers were subjected to compression molding to produce a bilayeredcompressed core containing 50 mg of compound A.

Step 4: Production of Semi-Permeable Membrane and Membrane Coating

Necessary amounts of polyethylene glycol 4000 and cellulose acetate(mass ratio of 6:94) were dissolved in a mixed solvent ofdichloromethane and methanol (mass ratio of 9:1) to prepare a coatingsolution having a solid concentration of 2% w/w. By using this solution,a film coating was formed so that the coating component was 5% w/w withrespect to the bilayered compressed core.

Step 5: Punching

A needle (27G) having a diameter of 0.4 mm was used to form orifices atthe drug layer side of the semi-permeable-membrane-coated tabletsprepared in Step 4, to prepare an osmotic pump type formulation as thepharmaceutical composition for modified release of the presentinvention.

Example 5 Preparation of Formulation Using Swelling Polymer

In the Examples (Examples 5A to 5C), as the pharmaceutical compositionfor modified release of the present invention, formulations 5A to 5Cusing a swelling polymer composed of the composition unit shown in Table7 were prepared.

Specifically, necessary amounts of compound A and polyethylene oxide(various types of Polyox, manufactured by DOW) were weighed out, andmixed sufficiently by using a mortar and a pestle so that they werehomogenized. The mixture was put into a die and subjected to compressionmolding by an oil press tabletting machine with a tabletting pressure of1000 kg/punch by using a punch having a diameter of 7 mm.

TABLE 7 Examples 5 A 5 B 5 C Compound A  50.0  50.0  50.0 Polyethyleneoxide 200.0 — — (Polyox WSR N-60K) Polyethylene oxide — 200.0 — (PolyoxWSR N-12K) Polyethylene oxide — — 200.0 (Polyox WSR N-205) Total (mg)250.0 250.0 250.0

Example 6 Preparation of Matrix Formulation Using Water-Soluble Polymer

In the Examples (Examples 6A to 6N), as the pharmaceutical compositionfor modified release of the present invention, matrix formulations 6A to6N composed of the composition units shown in Tables 8 and 9 wereprepared.

Specifically, necessary amounts of compound A and various additives[hypromellose (manufactured by Shin-Etsu Chemical Co. Ltd) orhydroxypropylcellulose (manufactured by Nippon Soda Co., Ltd.)] wereweighed out, and mixed sufficiently by using a mortar and a pestle sothat they were homogenized. The mixture was put into a die and subjectedto compression molding by an oil press tabletting machine with atabletting pressure of 1000 kg/punch.

TABLE 8 Examples 6 A 6 B 6 C 6 D 6 E 6 F Compound A 100.0 100.0 100.0100.0 100.0 100.0 Hypromellose 200.0 — —  50.0 — — (METLOSE SR90SH-100SR) Hypromellose — 200.0 — —  25.0 — (METLOSE SR 90SH- 4000SR)Hypromellose — — 200.0 — —  25.0 (METLOSE SR 90SH- 15000SR) Total (mg)300.0 300.0 300.0 150.0 125.0 125.0

TABLE 9 Examples 6 G 6 H 6 I 6 J 6 K 6 L 6 M 6 N Compound A 100.0 100.0100.0 100.0 100.0 100.0 100.0 100.0 Hydroxypropyl — — — —  50.0 — — —cellulose (HPC-L) Hydroxypropyl 200.0 — 100.0  50.0 —  25.0 — —cellulose (HPC-M) Hydroxypropyl — 200.0 — — — —  25.0  10.0 cellulose(HPC-H) Total (mg) 300.0 300.0 200.0 150.0 150.0 125.0 125.0 110.0

Example 7 Preparation of Modified Release Formulation with CoatingMembrane

In the Examples (Examples 7A to 7E), as the pharmaceutical compositionfor modified release of the present invention, modified releaseformulations 7A to 7E with a coating membrane composed of thecomposition unit shown in Table 10 were prepared.

Specifically, firstly, necessary amounts of the compound A and additivesof a core tablet were weighed out, and mixed sufficiently by using amortar and a pestle so that they were homogenized. The mixture was putinto a die and subjected to compression molding by an oil presstabletting machine with a tabletting pressure of 1000 kg/punch toproduce each core tablet. Additionally, necessary amounts of filmcoating components [as aminoalkyl methacrylate copolymer RS, varioustypes of Eudragit, manufactured by Degussa corporation; and asHypromellose, TC-5 E manufactured by Shin-Etsu Chemical Co. Ltd] weredissolved/dispersed in ethanol to prepare each coating solution having asolid concentration of 10% w/w. By using each solution, film coating wasconducted so that the coating component had a prescribed amount withrespect to the core tablet.

TABLE 10 Examples 7 A 7 B 7 C 7 D 7 E Core tablet Compound A 100.0 100.0100.0 100.0 100.0 Mannitol 100.0 — — — — Polyethylene glycol 8000 —200.0 200.0 200.0 200.0 Subtotal (mg) 200.0 300.0 300.0 300.0 300.0 Filmcoat Aminoalkyl methacrylate — —  15.0  30.0  22.5 Copolymer RS(Eudragit RL PO) Aminoalkyl methacrylate  10.0  12.0 — — — Copolymer RS(Eudragit RS PO) Hypromellose (TC-5 E) — — — —  7.5 Subtotal (mg)  10.0 12.0  15.0  30.0  30.0 Total (mg) 210.0 312.0 315.0 330.0 330.0

Example 8 Preparation of Matrix Formulation Using Insoluble PolymerExamples 8A to 8C

As the pharmaceutical composition for modified release of the presentinvention, matrix formulations (tablets) 8A to 8C composed of thecomposition unit shown in Table 11 were prepared.

Specifically, necessary amounts of the compound A and ethylcellulose(Ethocel 10 premium, manufactured by DOW) were weighed out, and mixedsufficiently by using a mortar and a pestle so that they werehomogenized. The mixture was put into a die and subjected to compressionmolding by an oil press tabletting machine with a tabletting pressure of1000 kg/punch.

TABLE 11 Examples 8 A 8 B 8 C Compound A 100.0 100.0 100.0Ethylcellulose 200.0 25.0 10.0 (Ethocel 10 premium) Total (mg) 300.0125.0 110.0

Examples 8D and 8E

As the pharmaceutical composition for modified release of the presentinvention, matrix formulations (granules) 8D to 8E composed of thecomposition unit shown in Table 12 were prepared.

Specifically, necessary amounts of the compound A and ethylcelluloseshown in Table 12 were weighed out, and mixed sufficiently by using amortar and a pestle so that they were homogenized. Furthermore, anappropriate amount of ethanol was added thereto, and the mixture wasstirred and mixed. The mixture was dried, and screened by using a sieveso as to remove coarse particles to prepare granule formulations 8D and8E for modified release as the pharmaceutical composition for modifiedrelease of the present invention.

TABLE 12 Examples 8 D 8 E Compound A 25.0 50.0 Ethylcellulose 75.0 100.0Total (mg) 100.0 150.0

Examples 8F and 8G

Necessary amounts of the compound A and microcrystalline cellulose shownin Table 13 were weighed out, and mixed sufficiently by using a mortarand a pestle so that they were homogenized. Furthermore, a prescribedamount of solution of ethylcellulose in ethanol was added thereto, andthe mixed solution was stirred and mixed. The mixture was dried andscreened by using a sieve so as to remove coarse particles to preparegranule formulations 8F and 8G for modified release as thepharmaceutical composition for modified release of the presentinvention.

TABLE 13 Examples 8 F 8 G Compound A 50.0 50.0 Microcrystallinecellulose — 50.0 Ethylcellulose  8.0 10.0 Total (mg) 58.0 110.0

Experimental Example 1 Dissolution Test of Sustained ReleaseHydrogel-Forming Formulation

A drug release property from each of the formulations prepared inExamples 1A to 1C was evaluated by the dissolution test, method 2(paddle method) described in the Japanese Pharmacopoeia. The test wascarried out using 900 mL of a USP phosphate buffer (pH 6.8) as a testsolution at a paddle rotating speed of 200 rpm. The drug concentrationin the test solution was measured every hour, and the drug releaseproperty was evaluated. The results are shown in Table 14 and FIG. 1.

TABLE 14 Examples 1 A 1 B 1 C Dissolution rate 54 15 27 1.5 hoursDissolution rate 80 31 52 2.5 hours Dissolution rate 99 66 95 7 hours

Experimental Example 2 Dissolution Test of Multi-Layered FormulationConsisting of Drug Core and Release-Controlling Layer which areGeometrically Arranged

A drug release property from each of the formulations prepared inExamples 2A to 2D was evaluated by the method described in ExperimentalExample 1. The results are shown in Table 15 and FIG. 2.

TABLE 15 Examples 2 A 2 B 2 C 2 D Dissolution rate 19 19 18 21 1.5 hoursDissolution rate 26 32 25 30 2.5 hours Dissolution rate 57 75 73 88 7hours

Experimental Example 3 Dissolution Test of Gel Formulation in which aPlurality of Gums is Combined

A drug release property from the formulation prepared in Example 3 wasevaluated by the method described in Experimental Example 1. The resultsare shown in FIG. 3. As a result, the dissolution rates after 1.5 hours,2.5 hours, and 7 hours were 11%, 18%, and 78%, respectively.

Experimental Example 4 Dissolution Test of Osmotic Pump Type Formulation

A drug release property from the formulation prepared in Example 4 wasevaluated by the method described in Experimental Example 1. The resultsare shown in FIG. 4. As a result, the dissolution rates after 1.5 hours,2.5 hours, and 7 hours were 21%, 43%, and 90%, respectively.

Experimental Example 5 Dissolution Test of Formulation Using SwellingPolymer

A drug release property from each of the formulations prepared inExamples 5A to 5C was evaluated by the method described in ExperimentalExample 1. The results are shown in Table 16 and FIG. 5.

TABLE 16 Examples 5 A 5 B 5 C Dissolution rate 13 20 26 1.5 hoursDissolution rate 23 38 47 2.5 hours Dissolution rate 67 91 96 7 hours

Experimental Example 6 Dissolution Test of Matrix Formulation UsingWater-Soluble Polymer

A drug release property from each of the formulations prepared inExamples 6A to 6N was evaluated by the method described in ExperimentalExample 1. The results are shown in Tables 17 and 18 and FIGS. 6 and 7.

TABLE 17 Examples 6 A 6 B 6 C 6 D 6 E 6 F 6 G Dissolution rate 18 7 6 3840 34 7 1.5 hours Dissolution rate 29 11 10 59 51 43 12 2.5 hoursDissolution rate 76 35 26 98 85 76 34   7 hours

TABLE 18 Examples 6 H 6 I 6 J 6 K 6 L 6 M 6 N Dissolution rate 6 10 1938 24 15 27 1.5 hours Dissolution rate 8 17 29 59 39 25 43 2.5 hoursDissolution rate 20 52 73 96 86 62 89   7 hours

Experimental Example 7 Dissolution Test of Modified Release Formulationwith Coating Membrane

A drug release property from each of the formulations, prepared inExamples 7A to 7E was evaluated by the method described in ExperimentalExample 1. The results are shown in Table 19 and FIG. 8.

TABLE 19 Examples 7 A 7 B 7 C 7 D 7 E Dissolution rate 1 3 5 5 42 1.5hours Dissolution rate 2 3 14 7 67 2.5 hours Dissolution rate 8 6 99 54104 7 hours

Experimental Example 8 Dissolution Test of Matrix Formulation UsingInsoluble Polymer

A drug release property from each of the formulations prepared inExamples 8A to 8C was evaluated by the method described in ExperimentalExample 1. The results are shown in Table 20 and FIG. 9.

TABLE 20 Examples 8 A 8 B 8 C Dissolution rate 12 22 28 1.5 hoursDissolution rate 17 32 42 2.5 hours Dissolution rate 38 69 86 7 hours

A drug release property from each of the formulations prepared inExamples 8D to 8G was evaluated by the method described in ExperimentalExample 1. The results are shown in Table 21 and FIG. 10.

TABLE 21 Examples 8 D 8 E 8 F 8 G Dissolution rate 51 45 67 66 1.5 hoursDissolution rate 57 50 77 75 2.5 hours Dissolution rate 69 60 92 91 7hours

Experimental Example 9 Pharmacokinetics (PK) Test of Immediate ReleaseFormulation (Capsule Formulation) in Human

An immediate release formulation (capsule formulation) containingcompound A was administered to healthy subjects in a fasted state,before 30 min from the intake of a meal, or after 30 min from the meal,and the drug concentration in the plasma was measured. The immediaterelease formulations (capsule formulations) containing 0.1 mg, 1 mg, 5mg, 20 mg, and 80 mg of the compound A were used in combinations asneeded so that the dose of compound A became 0.1 mg, 1 mg, 3 mg, 10 mg,30 mg, 100 mg, 160 mg, 240 mg, and 340 mg.

Results are shown in FIG. 11. When the maximum plasma concentration(Cmax) of compound A and the increase in heart rate from the base linewere analyzed, a positive correlation was observed.

Experimental Example 10 Pharmacokinetics (PK) Test of Sustained ReleaseHydrogel-Forming Formulation in Human

The pharmaceutical composition for modified release of the presentinvention prepared in Example 1A or 1B (containing compound A in anamount corresponding to 200 mg) was administered to healthy subjects ina fasted state (Fasted) or after 30 min from the intake of a meal (Fed),and the drug concentration in the plasma was measured. On the otherhand, two capsules of the pharmaceutical composition (conventionalformulation) (containing compound A in an amount corresponding to 160mg) of Comparative Example 1 was administered to healthy subjects in afasted state or after 30 min from the intake of a meal, and the drugconcentration in the plasma was measured.

The results in the pharmaceutical composition for modified release ofthe present invention prepared in Example 1A are shown in FIG. 12, andthe results in the pharmaceutical composition for modified release ofthe present invention prepared in Example 1B are shown in FIG. 13,respectively.

With respect to the conventional formulation, the rate of decrease ofCmax in the fed state was 67%, in comparison with that in the fastedstate, and the rate of decrease of AUC was 47% (Cmax in the fasted statewas approximately three times higher than that in the fed state). Withrespect to the pharmaceutical compositions for modified release (1A and1B) of the present invention, the rates of decrease of Cmax in the fedstate were 4% and 10%, in comparison with those in the fasted state, andthe rates of decrease of AUC were 10% and −4%. These results indicatedthat the reductions of Cmax and AUC caused by food intake could besignificantly alleviated by the pharmaceutical composition for modifiedrelease of the present invention.

Furthermore, the maximum plasma concentration after the administrationof the pharmaceutical composition for modified release prepared inExample 1A of the present invention was 274 ng/mL and 264 ng/mL in thefasted state and in the fed state, respectively. Similarly, in Example1B, they were 155 ng/mL and 140 ng/mL, respectively. Furthermore, theincrease in heart rate is 13 bpm or less in both.

INDUSTRIAL APPLICABILITY

According to the present invention, a pharmaceutical composition formodified release which is not affected by the effects of food intake andexhibits a decreased change in AUC or Cmax by controlling the releasingrate of the active ingredient can be provided.

As above, the present invention was explained with reference toparticular embodiments, but modifications and improvements obvious tothose skilled in the art are included in the scope of the presentinvention.

The invention claimed is:
 1. A pharmaceutical composition for modifiedrelease comprising a drug, which is(R)-2-(2-aminothiazol-4-yl)-4′-[(2-[2-hydroxy-2-phenylethyl)amino]ethyl]aceticacid anilide or a pharmaceutically acceptable salt thereof, and acarrier for a sustained release pharmaceutical composition, wherein adissolution rate of the drug from the composition is less than 85% after30 minutes from the beginning of a dissolution test, and saidpharmaceutical composition is selected from the group consisting of agel formulation in which a plurality of gums is combined, an osmoticpump type formulation, a formulation utilizing a swelling polymer, amatrix formulation utilizing a water-soluble polymer and a matrixformulation utilizing an insoluble polymer.
 2. The pharmaceuticalcomposition for modified release according to claim 1, wherein adissolution rate is 75% or less after 1.5 hours from the beginning ofthe dissolution test.
 3. The pharmaceutical composition for modifiedrelease according to claim 1, wherein the dissolution rate is 75% orless after 1.5 hours from the beginning the dissolution test, and adissolution rate is 75% to 100% after 7 hours from the beginning of thedissolution test.
 4. A method of reducing an effect of food intake,comprising the step of administering a pharmaceutical compositioncomprising a drug, which is(R)-2-(2-aminothiazol-4-yl)-4′-[(2-hydroxy-2-phenylethyl)amino]ethyl]aceticacid anilide or a pharmaceutically acceptable salt thereof, and acarrier for a sustained release pharmaceutical composition, wherein adissolution rate of the drug from the composition is less than 85% after30 minutes from the beginning of a dissolution test, and saidpharmaceutical composition is selected from the group consisting of agel formulation in which a plurality of gums is combined, an osmoticpump type formulation, a formulation utilizing a swelling polymer, amatrix formulation utilizing a water-soluble polymer and a matrixformulation utilizing an insoluble polymer.
 5. The method of reducing aneffect of food intake according to claim 4, wherein a dissolution rateis 75% or less after 1.5 hours form the beginning of the dissolutiontest.
 6. The method of reducing an effect of food intake according toclaim 4, wherein the dissolution rate is 75% or less after 1.5 hoursfrom the beginning the dissolution test, and a dissolution rate is 75%to 100% after 7 hours from the beginning of the dissolution test.
 7. Thepharmaceutical composition for modified release according to claim 1,which is the gel formulation in which a plurality of gums is combined,wherein the carrier for a sustained release pharmaceutical compositionis a gum base which is a sustained release filler comprising ahomopolysaccharide which can form a crosslinkage with aheteropolysaccharide gum when exposed to the heteropolysaccharide gumand environmental fluids.
 8. The pharmaceutical composition for modifiedrelease according to claim 7, wherein the sustained release fillerfurther comprises calcium sulfate and/or a water-soluble base.
 9. Thepharmaceutical composition for modified release according to claim 1,which is the osmotic pump type formulation, wherein a bilayeredcompressed core consisting of a drug layer and a push layer is coatedwith a semipermeable membrane.
 10. The pharmaceutical composition formodified release according to claim 9, wherein the push layer containsone or more osmotic active components.
 11. The pharmaceuticalcomposition for modified release according to claim 1, which is theformulation utilizing a swelling polymer, wherein the swelling polymeris a water-soluble high molecular weight polymer which swells uponimbibition of water.
 12. The pharmaceutical composition for modifiedrelease according to claim 11, wherein the swelling polymer has a weightaverage molecular weight of approximately 4,500,000 or more.
 13. Thepharmaceutical composition for modified release according to claim 1,which is the matrix formulation utilizing a water-soluble polymer,wherein the drug is homogenously dispersed in one or more water-solublepolymers.
 14. The pharmaceutical composition for modified releaseaccording to claim 13, wherein the water-soluble polymer is graduallygelled, eroded, dissolved, and/or disintegrated when exposed to anenvironmental fluid.
 15. The pharmaceutical composition for modifiedrelease according to claim 1, which is the modified release formulationwith a coating membrane, wherein a coating liquid contains a membraneforming agent, a plasticizer, a water-soluble base, or a dispersingagent.
 16. The pharmaceutical composition for modified release accordingto claim 1, which is the matrix formulation utilizing an insolublepolymer, wherein the drug is uniformly dispersed in a water-insolublepolymer.
 17. The pharmaceutical composition for modified releaseaccording to claim 16, wherein the water-insoluble polymer is selectedfrom the group consisting of dibenzyl phthalate, dihexyl phthalate,butyl octyl phthalate, beeswax, carnauba wax, cetyl alcohol, cetylstearyl alcohol, glyceryl behenate, lipids, fats, resins, cellulosederivatives, polyacrylate derivatives, polymethacrylate derivatives,hydroxypropylmethyl cellulose acetate succinate, polylactic acid, andpolyglycolic acid.